Fix problem reading credential mapping template after refactoring (#769)

Author: rakillen

core/src/main/python/wlsdeploy/tool/util/targets/file_template_helper.py

@@ -35,7 +35,7 @@ def create_file_from_resource(resource_path, template_hash, output_file, excepti
     """
     _method_name = 'create_file_from_resource'
 
-    template_stream = FileUtils.getFileAsStream(resource_path)
+    template_stream = FileUtils.getResourceAsStream(resource_path)
     if template_stream is None:
         ex = exception_helper.create_exception(exception_type, 'WLSDPLY-01661', resource_path)
         __logger.throwing(ex, class_name=__class_name, method_name=_method_name)