Merge branch 'KOP-2884-Mapping-von-Antragsteller' into 'main'

...based/formsolutions/FormSolutionsAntragstellerMapper.java

...ebased/formsolutions/FormSolutionsEngineBasedAdapter.java

.../enginebased/formsolutions/FormSolutionsHeaderMapper.java

...ginebased/formsolutions/mapper/FSAntragstellerMapper.java

...d/formsolutions/AntragstellerStringValuesTestFactory.java

...ntik/enginebased/formsolutions/FSFormDataTestFactory.java

...d/formsolutions/FormSolutionsAntragstellerMapperTest.java

.../formsolutions/FormSolutionsEngineBasedAdapterITCase.java

...ed/formsolutions/FormSolutionsEngineBasedAdapterTest.java

.../enginebased/formsolutions/IdentifierValueParserTest.java

...based/formsolutions/mapper/FSAntragstellerMapperTest.java

...t/resources/Weihnachtsmarkt_Standanmeldung_form-data.json