Get proper parameters with prefixes without dot separator (ros2#455)

Signed-off-by: Brian Ezequiel Marchi <[email protected]>

Author: BMarchi

rclpy/rclpy/parameter_service.py

@@ -90,6 +90,9 @@ def _list_parameters_callback(self, request, response):
                 names_with_prefixes.append(name)
                 continue
             elif request.prefixes:
+                for prefix in request.prefixes:
+                    if name.startswith(prefix):
+                        response.result.names.append(name)
                 continue
             else:
                 response.result.names.append(name)