chore(tier4_simulator_component): change namespace1 to camera7 (#426)

Signed-off-by: Tomohito Ando <tomohito.ando@tier4.jp>

autoware_launch/launch/components/tier4_simulator_component.launch.xml

@@ -28,6 +28,7 @@
     <arg name="initial_engage_state" value="$(var initial_engage_state)"/>
     <arg name="vehicle_info_param_file" value="$(var vehicle_info_param_file)"/>
     <arg name="external/traffic_signals" value="/v2x/traffic_signals"/>
+    <arg name="namespace1" value="camera7"/>
 
     <arg name="fault_injection_param_path" value="$(find-pkg-share autoware_launch)/config/simulator/fault_injection.param.yaml"/>
     <arg