Consolidate mavros_mission_tests.yml and mavros_offboard_tests.yml into a
single mavros_tests.yml with a matrix strategy. Switch from docker-in-docker
with px4-dev-ros-melodic to a native container using px4-dev-ros-noetic,
enabling ccache and composite actions (setup-ccache, build-gazebo-sitl,
save-ccache). Migrate all five MAVROS Python test files from Python 2 to
Python 3 (remove six/xrange, from __future__ imports, replace px4tools
with pyulog for estimator analysis). Bump git-auto-commit-action from v4
to v7 in ekf_update_change_indicator.yml.
Signed-off-by: Ramon Roche <mrpollo@gmail.com>
