Bump runc to v1.2.1

[brandond]

Runc v1.2 is out, we should update to it.

[mdrahman-suse]

Validated all the backports on release branch commits

[ClashTheBunny]

This change is causing issues with VPNs.

Is it possible to revert this change in a point release? Going to a major API breaking change at a point release seems like a bad idea. There is also talk of reverting the change on the runc PR.

See my other comment about the security implications of this:
opencontainers/runc#3468 (comment)

[brandond]

No. But if/when there is a new version of runc available we can update again.

Please contain discussion to the runc issue or #11429 in this project.