fix(simple-action-server): info log instead of warn on cancel (ros-navigation#4684) (ros-navigation#4686)

Cancelling a goal is nominal behavior and therefore it should not log
warning.

Signed-off-by: Rein Appeldoorn <rein.appeldoorn@nobleo.nl>
(cherry picked from commit d4c3faa)

Co-authored-by: Rein Appeldoorn <rein.appeldoorn@nobleo.nl>

Author: mergify[bot]

nav2_util/include/nav2_util/simple_action_server.hpp

@@ -582,7 +582,7 @@ class SimpleActionServer
 
     if (is_active(handle)) {
       if (handle->is_canceling()) {
-        warn_msg("Client requested to cancel the goal. Cancelling.");
+        info_msg("Client requested to cancel the goal. Cancelling.");
         handle->canceled(result);
       } else {
         warn_msg("Aborting handle.");