KOP-2149 sendMessage: Implement sending and support undefined businessScenarios

src/main/java/de/ozgcloud/xta/client/XtaClient.java

...ain/java/de/ozgcloud/xta/client/mapper/RequestMapper.java

...in/java/de/ozgcloud/xta/client/mapper/ResponseMapper.java

...java/de/ozgcloud/xta/client/model/XtaMessageMetaData.java

...st/java/de/ozgcloud/xta/client/XtaClientManualITCase.java

src/test/java/de/ozgcloud/xta/client/XtaClientTest.java

.../java/de/ozgcloud/xta/client/XtaMessageExampleLoader.java

...t/java/de/ozgcloud/xta/client/core/RequestMapperTest.java

.../java/de/ozgcloud/xta/client/core/ResponseMapperTest.java

...gcloud/xta/client/factory/MessageMetaDataTestFactory.java

...oud/xta/client/factory/XtaMessageMetaDataTestFactory.java

src/test/resources/messages/dfoerdermittel/xta-message.yaml

...t/resources/messages/versammlungsanzeige/xta-message.yaml