chore(control_validator): add maintainer (autowarefoundation#6238)

Add new maintainers to package.xml

Signed-off-by: kyoichi-sugahara <kyoichi.sugahara@tier4.jp>

Author: kyoichi-sugahara

control/control_validator/package.xml

@@ -7,6 +7,9 @@
   <maintainer email="kyoichi.sugahara@tier4.jp">Kyoichi Sugahara</maintainer>
   <maintainer email="takamasa.horibe@tier4.jp">Takamasa Horibe</maintainer>
   <maintainer email="makoto.kurihara@tier4.jp">Makoto Kurihara</maintainer>
+  <maintainer email="mamoru.sobue@tier4.jp">Mamoru Sobue</maintainer>
+  <maintainer email="takayuki.murooka@tier4.jp">Takayuki Murooka</maintainer>
+
   <license>Apache License 2.0</license>
 
   <author email="kyoichi.sugahara@tier4.jp">Kyoichi Sugahara</author>