Add DoNotMockRecords to warn against mocking record data objects

[ralstonba]

Overview

Enhance the Java programming language with records, which are classes that act as transparent carriers for immutable data. Records can be thought of as nominal tuples.

Records are typically used as simple wrappers of data without any methods or complex behavior requiring external dependencies or expensive IO operations. As such, they should (almost) never be mocked, and instead a real instance should be used instead.

Details

The class hierarchy has changed from

|- AbstractMockChecker
  |-- DoNotMockAutoValue
  |-- DoNotMockChecker

to

|- AbstractMockChecker
  |-- DoNotMockRecords
  |-- AbstractAnnotationMockChecker
    |-- DoNotMockAutoValue
    |-- DoNotMockChecker

This was because AbstractMockChecker assumed that only annotations would be used in determining that a class should not be mocked. The majority of AbstractAnnotationMockChecker is a straight lift and shift of the original AbstractMockChecker.

Open Questions

• ElementKind.RECORD results in an IDE error in Intellij as it is annotated with @since 16, suggesting that the language level of the module be changed. This does not cause issues with complilation, but as I am entirely new to projects that deal with the AST I am wondering if there is a better approach here.

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[ralstonba]

Signed CLA