Make AwsV4FamilyHttpSigner a sub-type of HttpSigner

[gosar]

Motivation and Context

AwsV4FamilyHttpSigner not being an actual HttpSigner could be confusing. This is a followup from offline discussion of #4396 (comment).

Modifications

• Make AwsV4FamilyHttpSigner extends HttpSigner, but use generic for Identity type, to leave the door open in case another implementation of V4 uses different type.
• Remove extends HttpSigner from the V4 and V4a signers.

Testing

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist

• I have read the CONTRIBUTING document
• Local run of mvn install succeeds
• My code follows the code style of this project
• My change requires a change to the Javadoc documentation
• I have updated the Javadoc documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed
• I have added a changelog entry. Adding a new entry must be accomplished by running the scripts/new-change script and following the instructions. Commit the new file created by the script in .changes/next-release with your changes.
• My change is to implement 1.11 parity feature and I have updated LaunchChangelog

License

• I confirm that this pull request can be released under the Apache 2 license

[sonarqubecloud]

SonarCloud Quality Gate failed.   

4 Bugs
0 Vulnerabilities
2 Security Hotspots
412 Code Smells

84.6% Coverage
3.8% Duplication

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