chore: organize maintainer (#858)

Signed-off-by: satoshi-ota <satoshi.ota928@gmail.com>

Author: satoshi-ota

planning/behavior_velocity_planner/autoware_behavior_velocity_stop_line_module/package.xml

@@ -7,13 +7,10 @@
 
   <maintainer email="yukinari.hisaki.2@tier4.jp">Yukinari Hisaki</maintainer>
   <maintainer email="satoshi.ota@tier4.jp">Satoshi Ota</maintainer>
-  <maintainer email="fumiya.watanabe@tier4.jp">Fumiya Watanabe</maintainer>
-  <maintainer email="zhe.shen@tier4.jp">Zhe Shen</maintainer>
-  <maintainer email="tomoya.kimura@tier4.jp">Tomoya Kimura</maintainer>
-  <maintainer email="shumpei.wakabayashi@tier4.jp">Shumpei Wakabayashi</maintainer>
 
   <license>Apache License 2.0</license>
 
+  <author email="fumiya.watanabe@tier4.jp">Fumiya Watanabe</author>
   <author email="yutaka.shimizu@tier4.jp">Yutaka Shimizu</author>
 
   <buildtool_depend>ament_cmake_auto</buildtool_depend>