OZG-6054 xta: Get messages with multiple identifiers

...va/de/ozgcloud/eingang/xta/WsHeaderAddingInterceptor.java

.../de/ozgcloud/eingang/xta/XtaCurrentIdentifierService.java

.../src/main/java/de/ozgcloud/eingang/xta/XtaProperties.java

...ter/src/main/java/de/ozgcloud/eingang/xta/XtaService.java

xta-adapter/src/main/resources/application-local.yml

...adapter/src/test/helm/xta_adapter_cronjob_basic_test.yaml

xta-adapter/src/test/helm/xta_adapter_cronjob_env_test.yaml

...apter/src/test/helm/xta_adapter_cronjob_volumes_test.yaml

.../ozgcloud/eingang/xta/XtaActiveIdentifierServiceTest.java

...src/test/java/de/ozgcloud/eingang/xta/XtaServiceTest.java

xta-adapter/src/test/resources/application-itcase.yml