refactor navigation2 docker - cleanup dependencies

[asimonov]

I suggest we cleanup navigation2 docker build, still keeping things on humble.
But remove gazebo and rviz dependencies from it.

Gazebo is better to install separately at a later stage, with a view of moving to Gazebo Harmonic. Currently gazebo classic is installed as dependency of nav2_system_tests.

Rviz is currently installed from apt and brings with it a lot of ros-humble*.

[Bckempa]

That's another item we should be tracking - how many package manager installs we require.

Recently we discussed moving user tools out of the main build and making various simulators into stacks, this seems like a reasonable step toward that.

[xfiderek]

hi @asimonov . this will be addressed as part of this #142

[asimonov]

@xfiderek yes, I discovered #142 after doing this work. it was created a while ago and from the name I thought it was just about selecting more stable release versions of repos, not refactor of entire dependency install.

I kind of like how you simplified dependencies of nav2 in PR #152

may be i will close/retract this one. let me do some testing of #152...