Fix rcl_parse_yaml_file() error handling. (#776) (#786)

It should not fini its output argument, silently invalidating the given pointer.

Signed-off-by: Michel Hidalgo <michel@ekumenlabs.com>

rcl_yaml_param_parser/src/parser.c

@@ -1801,12 +1801,7 @@ bool rcl_parse_yaml_file(
     allocator.deallocate(ns_tracker.parameter_ns, allocator.state);
   }
 
-  if (RCUTILS_RET_OK != ret) {
-    rcl_yaml_node_struct_fini(params_st);
-    return false;
-  }
-
-  return true;
+  return RCUTILS_RET_OK == ret;
 }
 
 ///