Fix failing CDATA tests on Windows.

CDATA is not marshalled with proper new line separator as reported in RHPAM-3057 jira.

If the issue is not planned to be fixed, there is a need to fix failing tests. Otherwise, this jira can be closed.

Acceptanca criteria

The folowing tests are passing on both Linux and Windows:
org.kie.workbench.common.stunner.bpmn.backend.service.diagram.BPMNDirectDiagramMarshallerTest class:

• testMarshallScriptTask
• testMarshallSequenceFlow
• testMarshallUserTaskAssignees