FINERACT-2474: Add Unit Tests for ClientReadPlatformServiceImpl

[nidhiii128]

Description

This PR introduces unit tests for ClientReadPlatformServiceImpl to improve code coverage and ensure logic reliability within the fineract-provider module.

Regression Testing Verification: The attached image shows the unit test successfully identifying a logic failure when the hierarchy search pattern is intentionally altered. This confirms the test effectively guards against logic regressions that the Java compiler would ignore.

Technical Details
Created ClientReadPlatformServiceImplTest using JUnit 5 and Mockito.
Covered the retrieveOne success scenario with mock data.
Verified error handling for ClientNotFoundException when the database returns no results.
Added validation testing for retrieveAll to ensure invalid search statuses are rejected correctly.
Applied Spotless formatting to match project standards.

Testing
Successfully ran ./gradlew :fineract-provider:test --tests "org.apache.fineract.portfolio.client.service.ClientReadPlatformServiceImplTest"

Verified local build with ./gradlew spotlessJavaCheck.

Checklist

Please make sure these boxes are checked before submitting your pull request - thanks!

• Write the commit message as per our guidelines
• Acknowledge that we will not review PRs that are not passing the build ("green") - it is your responsibility to get a proposed PR to pass the build, not primarily the project's maintainers.
• Create/update unit or integration tests for verifying the changes made.
• Follow our coding conventions.
• Add required Swagger annotation and update API documentation at fineract-provider/src/main/resources/static/legacy-docs/apiLive.htm with details of any API changes
• This PR must not be a "code dump". Large changes can be made in a branch, with assistance. Ask for help on the developer mailing list.

Your assigned reviewer(s) will follow our guidelines for code reviews.

[airajena]

Please squash your commits.

[nidhiii128]

Please squash your commits.

@airajena done

[IOhacker]

@nidhiii128 please make sure that the PR title and the Jira ticket title are the same.

[Aman-Mittal]

@nidhiii128
rename your PR title from
FINERACT-2474 : Add Unit Tests for ClientReadPlatformServiceImpl
to
FINERACT-2474: Add Unit Tests for ClientReadPlatformServiceImpl

Check is failing due to space between FINERACT-2474 :

[adamsaghy]

* What went wrong:
Execution failed for task ':fineract-provider:spotlessJavaCheck'.
> The following files had format violations:
      src/test/java/org/apache/fineract/portfolio/client/service/ClientReadPlatformServiceImplTest.java
          @@ -130,5 +130,3 @@
           ········});
           ····}
           }
          -
          -
  Run './gradlew :fineract-provider:spotlessApply' to fix these violations.

[nidhiii128]

* What went wrong:
Execution failed for task ':fineract-provider:spotlessJavaCheck'.
> The following files had format violations:
      src/test/java/org/apache/fineract/portfolio/client/service/ClientReadPlatformServiceImplTest.java
          @@ -130,5 +130,3 @@
           ········});
           ····}
           }
          -
          -
  Run './gradlew :fineract-provider:spotlessApply' to fix these violations.

@adamsaghy Done! I've run ./gradlew spotlessApply and amended the commit. It should be clean now. Thanks for the help with the title!