Removed 1 unnecessary stubbing in AbstractArtifactTest.java

[ARUS2023]

Testing done

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In our analysis of the project, we observed that

1. the stubbing in the AbstractArtifactTest.before is created but never executed by 3 tests: VersionParameterDefinitionTest.testGetVersions, VersionParameterDefinitionTest.testGetVersionParameterValue, and VersionParameterDefinitionTest.testEscapeInputs.

Unnecessary stubbings are stubbed method calls that were never realized during test execution. Mockito recommends to remove unnecessary stubbings (https://www.javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/exceptions/misusing/UnnecessaryStubbingException.html).

We propose below a solution to remove the unnecessary stubbing.