Resolve Pitest suppression for EmptyLineSeperator

[Kevin222004]

Related to #7797

kill mutation

checkstyle/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml

Lines 30 to 37 in 49a93e4

	<mutation unstable="false">
	<sourceFile>EmptyLineSeparatorCheck.java</sourceFile>
	<mutatedClass>com.puppycrawl.tools.checkstyle.checks.whitespace.EmptyLineSeparatorCheck</mutatedClass>
	<mutatedMethod>getViolationAstForPackage</mutatedMethod>
	<mutator>org.pitest.mutationtest.engine.gregor.mutators.experimental.NakedReceiverMutator</mutator>
	<description>replaced call to com/puppycrawl/tools/checkstyle/api/DetailAST::getNextSibling with receiver</description>
	<lineContent>DetailAST nextElement = ast.getNextSibling();</lineContent>
	</mutation>

and

checkstyle/.ci/pitest-suppressions/pitest-whitespace-suppressions.xml

Lines 57 to 64 in 49a93e4

	<mutation unstable="false">
	<sourceFile>EmptyLineSeparatorCheck.java</sourceFile>
	<mutatedClass>com.puppycrawl.tools.checkstyle.checks.whitespace.EmptyLineSeparatorCheck</mutatedClass>
	<mutatedMethod>isLineEmptyAfterPackage</mutatedMethod>
	<mutator>org.pitest.mutationtest.engine.gregor.mutators.experimental.NakedReceiverMutator</mutator>
	<description>replaced call to com/puppycrawl/tools/checkstyle/api/DetailAST::getNextSibling with receiver</description>
	<lineContent>DetailAST nextElement = ast.getNextSibling();</lineContent>
	</mutation>

[nitishfy]

I'm working on this.

[rnveach]

This will be resolved under #12601 so I am closing this.