mash generates recipes with catkin build_type

[robwoolley]

Mash defaults to a build_type of 'catkin' for the rsl recipe. This happens because the rsl recipe does not specifiy a build_type in its package.xml: https://github.com/PickNikRobotics/RSL/blob/main/package.xml

This happens because the catkin_pkg module defaults to setting build_type to catkin if unspecified: https://github.com/ros-infrastructure/catkin_pkg/blob/921fc9e64af6b78fe84cd9dbb92a4d660c3dafa4/src/catkin_pkg/package.py#L150

Super Flore detects when the build_type is 'catkin' for ROS 2 builds and sets it to 'ament_cmake' instead: https://github.com/ros-infrastructure/superflore/blob/b10efe80de4abec269f8e4bd7e18d8bb737984bd/superflore/generators/bitbake/yocto_recipe.py#L109

The temporary workaround is to add a bbappend to override ROS_BUILD_TYPE for rsl.