Merge branch 'KOP-2884-Cleanup' into 'main'

...ebased/formsolutions/FormSolutionsEngineBasedAdapter.java

.../enginebased/formsolutions/FormSolutionsHeaderMapper.java

...k/enginebased/formsolutions/FormSolutionsPanelMapper.java

...ntik/enginebased/formsolutions/IdentifierValueParser.java

...d/formsolutions/FormSolutionsAntragstellerMapperTest.java

.../formsolutions/FormSolutionsEngineBasedAdapterITCase.java

...ed/formsolutions/FormSolutionsEngineBasedAdapterTest.java

...nebased/formsolutions/FormSolutionsHeaderTestFactory.java

...ginebased/formsolutions/FormSolutionsPanelMapperTest.java

.../enginebased/formsolutions/IdentifierValueParserTest.java