resource/aws_eip: Default to default domain when vpc not set

[gdavison]

Default to default domain when vpc not set. standard in EC2-Classic, vpc otherwise

Relates #26525
Relates #26666
Relates #23625

Output from acceptance testing:

$ make testacc PKG=ec2 TESTS=TestAccEC2EIP

    ec2_eip_test.go:424: Environment variable AWS_EC2_EIP_PUBLIC_IPV4_POOL is not set
--- SKIP: TestAccEC2EIP_PublicIPv4Pool_custom (0.00s)
    ec2_eip_test.go:566: Environment variable AWS_EC2_EIP_BYOIP_ADDRESS is not set
--- SKIP: TestAccEC2EIP_BYOIPAddress_custom (0.00s)
    ec2_eip_test.go:594: Environment variable AWS_EC2_EIP_BYOIP_ADDRESS is not set
--- SKIP: TestAccEC2EIP_BYOIPAddress_customWithPublicIPv4Pool (0.00s)
    acctest.go:1346: skipping since no Outposts found
--- SKIP: TestAccEC2EIPDataSource_customerOwnedIPv4Pool (1.72s)
    wavelength_carrier_gateway_test.go:196: skipping since no Wavelength Zones are available
--- SKIP: TestAccEC2EIPDataSource_carrierIP (0.07s)
--- PASS: TestAccEC2EIP_disappears (79.49s)
--- PASS: TestAccEC2EIPDataSource_filter (93.29s)
--- PASS: TestAccEC2EIPDataSource_publicIP (95.68s)
--- PASS: TestAccEC2EIP_NetworkInterface_twoEIPsOneInterface (111.14s)
    wavelength_carrier_gateway_test.go:196: skipping since no Wavelength Zones are available
--- SKIP: TestAccEC2EIP_carrierIP (0.26s)
    ec2_classic.go:62: this test can only run in EC2-Classic, platforms available in us-east-1: ["VPC"]
--- SKIP: TestAccEC2EIPAssociation_classic (3.67s)
--- PASS: TestAccEC2EIP_noVPC (117.52s)
--- PASS: TestAccEC2EIP_basic (117.88s)
--- PASS: TestAccEC2EIP_networkInterface (136.89s)
    acctest.go:1346: skipping since no Outposts found
--- SKIP: TestAccEC2EIP_customerOwnedIPv4Pool (0.55s)
--- PASS: TestAccEC2EIPDataSource_id (95.92s)
--- PASS: TestAccEC2EIPAssociation_basic (197.76s)
    ec2_classic.go:62: this test can only run in EC2-Classic, platforms available in us-east-1: ["VPC"]
--- SKIP: TestAccEC2EIP_Instance_ec2Classic (0.00s)
--- PASS: TestAccEC2EIP_instance (206.65s)
--- PASS: TestAccEC2EIPDataSource_instance (211.27s)
--- PASS: TestAccEC2EIPDataSource_networkInterface (132.06s)
--- PASS: TestAccEC2EIPDataSource_tags (115.42s)
--- PASS: TestAccEC2EIPAssociation_networkInterface (146.10s)
--- PASS: TestAccEC2EIP_networkBorderGroup (150.25s)
--- PASS: TestAccEC2EIP_Instance_notAssociated (290.66s)
--- PASS: TestAccEC2EIPAssociation_spotInstance (198.06s)
--- PASS: TestAccEC2EIPsDataSource_basic (126.28s)
--- PASS: TestAccEC2EIP_tags (302.21s)
--- PASS: TestAccEC2EIP_Instance_reassociate (304.82s)
--- PASS: TestAccEC2EIPAssociation_instance (195.98s)
--- PASS: TestAccEC2EIP_BYOIPAddress_default (113.81s)
--- PASS: TestAccEC2EIP_PublicIPv4Pool_default (109.46s)
--- PASS: TestAccEC2EIPAssociation_disappears (150.53s)
--- PASS: TestAccEC2EIP_Instance_associatedUserPrivateIP (359.90s)
--- PASS: TestAccEC2EIP_association (374.52s)

[ewbankkit]

LGTM 🚀.

% make testacc TESTARGS='-run=TestAccEC2EIP_' PKG=ec2 ACCTEST_PARALLELISM=3
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./internal/service/ec2/... -v -count 1 -parallel 3  -run=TestAccEC2EIP_ -timeout 180m
=== RUN   TestAccEC2EIP_basic
=== PAUSE TestAccEC2EIP_basic
=== RUN   TestAccEC2EIP_disappears
=== PAUSE TestAccEC2EIP_disappears
=== RUN   TestAccEC2EIP_noVPC
=== PAUSE TestAccEC2EIP_noVPC
=== RUN   TestAccEC2EIP_tags
=== PAUSE TestAccEC2EIP_tags
=== RUN   TestAccEC2EIP_instance
=== PAUSE TestAccEC2EIP_instance
=== RUN   TestAccEC2EIP_Instance_reassociate
=== PAUSE TestAccEC2EIP_Instance_reassociate
=== RUN   TestAccEC2EIP_Instance_associatedUserPrivateIP
=== PAUSE TestAccEC2EIP_Instance_associatedUserPrivateIP
=== RUN   TestAccEC2EIP_Instance_notAssociated
=== PAUSE TestAccEC2EIP_Instance_notAssociated
=== RUN   TestAccEC2EIP_networkInterface
=== PAUSE TestAccEC2EIP_networkInterface
=== RUN   TestAccEC2EIP_NetworkInterface_twoEIPsOneInterface
=== PAUSE TestAccEC2EIP_NetworkInterface_twoEIPsOneInterface
=== RUN   TestAccEC2EIP_association
=== PAUSE TestAccEC2EIP_association
=== RUN   TestAccEC2EIP_PublicIPv4Pool_default
=== PAUSE TestAccEC2EIP_PublicIPv4Pool_default
=== RUN   TestAccEC2EIP_PublicIPv4Pool_custom
    ec2_eip_test.go:424: Environment variable AWS_EC2_EIP_PUBLIC_IPV4_POOL is not set
--- SKIP: TestAccEC2EIP_PublicIPv4Pool_custom (0.00s)
=== RUN   TestAccEC2EIP_customerOwnedIPv4Pool
=== PAUSE TestAccEC2EIP_customerOwnedIPv4Pool
=== RUN   TestAccEC2EIP_networkBorderGroup
=== PAUSE TestAccEC2EIP_networkBorderGroup
=== RUN   TestAccEC2EIP_carrierIP
=== PAUSE TestAccEC2EIP_carrierIP
=== RUN   TestAccEC2EIP_BYOIPAddress_default
=== PAUSE TestAccEC2EIP_BYOIPAddress_default
=== RUN   TestAccEC2EIP_BYOIPAddress_custom
    ec2_eip_test.go:566: Environment variable AWS_EC2_EIP_BYOIP_ADDRESS is not set
--- SKIP: TestAccEC2EIP_BYOIPAddress_custom (0.00s)
=== RUN   TestAccEC2EIP_BYOIPAddress_customWithPublicIPv4Pool
    ec2_eip_test.go:594: Environment variable AWS_EC2_EIP_BYOIP_ADDRESS is not set
--- SKIP: TestAccEC2EIP_BYOIPAddress_customWithPublicIPv4Pool (0.00s)
=== RUN   TestAccEC2EIP_Instance_ec2Classic
=== PAUSE TestAccEC2EIP_Instance_ec2Classic
=== CONT  TestAccEC2EIP_basic
=== CONT  TestAccEC2EIP_NetworkInterface_twoEIPsOneInterface
=== CONT  TestAccEC2EIP_networkBorderGroup
--- PASS: TestAccEC2EIP_networkBorderGroup (20.39s)
=== CONT  TestAccEC2EIP_Instance_reassociate
--- PASS: TestAccEC2EIP_basic (20.49s)
=== CONT  TestAccEC2EIP_networkInterface
--- PASS: TestAccEC2EIP_NetworkInterface_twoEIPsOneInterface (30.28s)
=== CONT  TestAccEC2EIP_Instance_notAssociated
--- PASS: TestAccEC2EIP_networkInterface (28.89s)
=== CONT  TestAccEC2EIP_Instance_associatedUserPrivateIP
--- PASS: TestAccEC2EIP_Instance_reassociate (129.16s)
=== CONT  TestAccEC2EIP_tags
--- PASS: TestAccEC2EIP_Instance_notAssociated (131.80s)
=== CONT  TestAccEC2EIP_instance
--- PASS: TestAccEC2EIP_tags (39.93s)
=== CONT  TestAccEC2EIP_noVPC
--- PASS: TestAccEC2EIP_noVPC (16.13s)
=== CONT  TestAccEC2EIP_disappears
--- PASS: TestAccEC2EIP_Instance_associatedUserPrivateIP (158.58s)
=== CONT  TestAccEC2EIP_BYOIPAddress_default
--- PASS: TestAccEC2EIP_disappears (12.65s)
=== CONT  TestAccEC2EIP_Instance_ec2Classic
    acctest.go:696: skipping tests; AWS_DEFAULT_REGION (us-west-2) does not equal us-east-1
--- SKIP: TestAccEC2EIP_Instance_ec2Classic (0.44s)
=== CONT  TestAccEC2EIP_PublicIPv4Pool_default
--- PASS: TestAccEC2EIP_BYOIPAddress_default (14.35s)
=== CONT  TestAccEC2EIP_customerOwnedIPv4Pool
    acctest.go:1346: skipping since no Outposts found
--- SKIP: TestAccEC2EIP_customerOwnedIPv4Pool (1.57s)
=== CONT  TestAccEC2EIP_carrierIP
--- PASS: TestAccEC2EIP_PublicIPv4Pool_default (16.56s)
=== CONT  TestAccEC2EIP_association
--- PASS: TestAccEC2EIP_carrierIP (18.46s)
--- PASS: TestAccEC2EIP_instance (126.63s)
--- PASS: TestAccEC2EIP_association (182.94s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/ec2	422.009s

[github-actions]

This functionality has been released in v4.30.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

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