* tests/vagrant: refactor vagrant smoke tests (#4484)

- updated `tests/TESTING.md`
- cgroup, snapshotter, and install tests all under tests/vagrant
- cgroup and snapshotter workflows trigger for all code changes on all branches (excluding markdown docs, install script, and other vagrant tests)
- install workflow triggers for relevant script and fixture changes, only on master or pull-requests that target it
- integration and unit test workflows should not trigger for install script changes nor anything under tests/vagrant
Co-authored-by: Jacob Blain Christen <jacob@rancher.com>
Signed-off-by: Jonnatan Jossemar Cordero <jonnatan.cordero@suse.com>

* Update CentOS 8 smoke vm's with vault repositories (#5092)

Update CentOS 8 smoke vm's with vault repositories

Problem: CentOS 8 reached its EOL alongside its public mirrors, making
all the smoke test fail at provisioning time.

Solution: Point all the CentOS repositories to vault.
Signed-off-by: Jonnatan Jossemar Cordero <jonnatan.cordero@suse.com>
Signed-off-by: Jonnatan Jossemar Cordero <jonnatan.cordero@suse.com>

* Update install GH action with release-1.22 branch

Problem: The install GH workflow enforces to be run agaisnt the main
branch as instead of a release one.

Solution: Update GH workflow and k3s install version accordingly to work
once it is run agaisnt release-1.22 branch
Signed-off-by: Jonnatan Jossemar Cordero <jonnatan.cordero@suse.com>
Co-authored-by: Jacob Blain Christen <jacob@rancher.com>