transfer: Improve diffs for policies

[YakDriver]

Description

Relations

Relates #23288

References

Output from Acceptance Testing

% make testacc TESTS="TestAccTransfer_serial/Access|TestAccTransfer_serial/User" PKG=transfer
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./internal/service/transfer/... -v -count 1 -parallel 20 -run='TestAccTransfer_serial/Access|TestAccTransfer_serial/User'  -timeout 180m
=== RUN   TestAccTransfer_serial
=== PAUSE TestAccTransfer_serial
=== CONT  TestAccTransfer_serial
=== RUN   TestAccTransfer_serial/Access
=== RUN   TestAccTransfer_serial/Access/disappears
=== RUN   TestAccTransfer_serial/Access/EFSBasic
=== RUN   TestAccTransfer_serial/Access/S3Basic
=== RUN   TestAccTransfer_serial/Access/S3Policy
=== RUN   TestAccTransfer_serial/User
=== RUN   TestAccTransfer_serial/User/basic
=== RUN   TestAccTransfer_serial/User/disappears
=== RUN   TestAccTransfer_serial/User/HomeDirectoryMappings
=== RUN   TestAccTransfer_serial/User/ModifyWithOptions
=== RUN   TestAccTransfer_serial/User/Posix
=== RUN   TestAccTransfer_serial/User/UserNameValidation
--- PASS: TestAccTransfer_serial (4503.13s)
    --- PASS: TestAccTransfer_serial/Access (3568.07s)
        --- PASS: TestAccTransfer_serial/Access/disappears (871.97s)
        --- PASS: TestAccTransfer_serial/Access/EFSBasic (832.12s)
        --- PASS: TestAccTransfer_serial/Access/S3Basic (972.23s)
        --- PASS: TestAccTransfer_serial/Access/S3Policy (891.76s)
    --- PASS: TestAccTransfer_serial/User (935.06s)
        --- PASS: TestAccTransfer_serial/User/basic (152.90s)
        --- PASS: TestAccTransfer_serial/User/disappears (160.28s)
        --- PASS: TestAccTransfer_serial/User/HomeDirectoryMappings (194.57s)
        --- PASS: TestAccTransfer_serial/User/ModifyWithOptions (215.42s)
        --- PASS: TestAccTransfer_serial/User/Posix (194.75s)
        --- PASS: TestAccTransfer_serial/User/UserNameValidation (17.14s)
PASS
ok  	github.com/hashicorp/terraform-provider-aws/internal/service/transfer	4505.133s

[github-actions]

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[github-actions]

This functionality has been released in v4.50.0 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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