NIFI-15151 Refactor Processor Tests using Shared Database Service

[exceptionfactory]

Summary

NIFI-15151 Refactors multiple tests in nifi-standard-processors using the shared EmbeddedDatabaseConnectionService to run unit tests with Apache Derby.

The refactored approach adds an abstract test class with lifecycle methods for creating and closing the embedded Apache Derby database using a JUnit temporary directory, and also provides methods to create new TestRunner instances with enabled DBCPService property settings applied.

The refactored approach reduces a significant amount of boilerplate code in multiple tests, but does not include a complete restructuring of duplicative table creation statements.

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  • JDK 21
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[pvillard31]

Thanks for the cleanup @exceptionfactory !