Add unit test in GovernanceRepositoryAPIImplTest

[pavanbaloju]

Fixes #28544 .

Changes proposed in this pull request:

• Adds unit test for persistJobOffsetInfo, getJobOffsetInfo methods

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• My code follows the code of conduct of this project.
• I have self-reviewed the commit code.
• I have (or in comment I request) added corresponding labels for the pull request.
• I have passed maven check locally : ./mvnw clean install -B -T1C -Dmaven.javadoc.skip -Dmaven.jacoco.skip -e.
• I have made corresponding changes to the documentation.
• I have added corresponding unit tests for my changes.

[zhaojinchao95]

Please fix ci, you need to check ci in your local environment，you can refer to : https://shardingsphere.apache.org/community/en/involved/conduct/code/

[pavanbaloju]

Please fix ci, you need to check ci in your local environment，you can refer to : https://shardingsphere.apache.org/community/en/involved/conduct/code/

I fixed the formatting and ./mvnw spotless:apply -Pcheck command shows build successful in local