Github action runners removed ubuntu-20.04 (actions/runner-images#11101) as of April 15, 2025. The current runner instances ubuntu-22.04/24.04 has cgroupv2 enabled by default and cgroupv1 is disabled. But to test the v1 shim, we need cgroupv1. Therefore the tests in release/1.7 and release/1.6 branch for
io.containerd.runc.v1 and io.containerd.runtime.v1.linux should be moved to vagrant where cgroupv1 can be enabled, so that it can be tested till EOL.

The tests in 1.7 branch was removed as part of #11722, but will have to be added back in vagrant tests

This is a tracking issue:

• release/1.6 [release/1.6] test: added runc v1 support in vagrant #11913
• release/1.7 [release/1.7] test: added runc v1 tests using vagrant #11896