Increase code coverage on dynamodb-enhanced module

[andreas-grafenberger]

Motivation and Context

The goal of this work is to increase unit, functional, and integration code coverage for the
aws-sdk-java-v2/services-custom/dynamodb-enhanced module.

Initial coverage:

• Class: 97%
• Method: 85%
• Line: 87%
• Branch: 64%

Target coverage:

• Class: ≥ 98%
• Method: ≥ 92%
• Line: ≥ 92%
• Branch: ≥ 85%

Achieved coverage:

• Class: 99%
• Method: 92%
• Line: 94%
• Branch: 91%

These results exceed the defined targets and significantly improve confidence in the correctness and stability of the enhanced DynamoDB module.

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Modifications

This pull request expands code coverage across the DynamoDB Enhanced Client by introducing new unit, functional, and integration tests targeting previously uncovered or partially covered code paths.

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Testing

• Existing test suites were executed without regression.
• New tests were added to specifically target uncovered branches and methods.
• All new and existing tests pass successfully.
• Coverage was measured locally after test execution to validate improvements.

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Screenshots

Initial coverage:

Achieved coverage:

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Types of changes

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

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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

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License

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