Update maintainer email (#487) (#492)

Signed-off-by: Carlos Agüero <caguero@openrobotics.org>
(cherry picked from commit 177b803)

Co-authored-by: Carlos Agüero <caguero@openrobotics.org>

Author: mergify[bot]

README.md

@@ -1,6 +1,6 @@
 # Gazebo Messages: Protobuf messages and functions for robot applications
 
-**Maintainer:** caguero AT openrobotics DOT org
+**Maintainer:** caguero AT honurobotics DOT com
 
 [![GitHub open issues](https://img.shields.io/github/issues-raw/gazebosim/gz-msgs.svg)](https://github.com/gazebosim/gz-msgs/issues)
 [![GitHub open pull requests](https://img.shields.io/github/issues-pr-raw/gazebosim/gz-msgs.svg)](https://github.com/gazebosim/gz-msgs/pulls)