Enable PMD rule LinguisticNaming

[pbludov]

https://pmd.github.io/latest/pmd_rules_java_codestyle.html#linguisticnaming

Part of #6536

[INFO] PMD Failure: com.puppycrawl.tools.checkstyle.checks.design.VisibilityModifierCheckTest:493
 Rule:LinguisticNaming Priority:3 Linguistics Antipattern - 
The variable 'isStarImport' indicates linguistically it is a boolean, but it is 'Method'.
[INFO] PMD Failure: com.puppycrawl.tools.checkstyle.checks.javadoc.AbstractTypeAwareCheckTest:50
 Rule:LinguisticNaming Priority:3 Linguistics Antipattern - 
The variable 'isSubclass' indicates linguistically it is a boolean, but it is 'Method'.
[INFO] PMD Failure: com.puppycrawl.tools.checkstyle.checks.metrics.NPathComplexityCheck:64 
Rule:LinguisticNaming Priority:3 Linguistics Antipattern - 
The field 'isAfterValues' indicates linguistically it is a boolean, but it is 'Deque'.

[romani]

The variable 'isStarImport' indicates linguistically it is a boolean, but it is 'Method'.

        final Method isStarImport = Whitebox.getMethod(VisibilityModifierCheck.class,
"isStarImport", DetailAST.class);

[romani]

Fix is merged