prevent Talos automatic rollback

[smira]

See https://github.com/siderolabs/talos/issues/9088

Talos has a feature which automatically reverts the version after an upgrade if the machine never reaches "ready" state.

This feature is good, but it might lead to undesired consequences (as in the ticket above), as the machine configuration might have been automatically updated for 1.7 already.

Omni should disable the revert behavior as soon as the machine connects back to Omni after an upgrade (with API running, so any rollback can be done now via an upgrade/downgrade flow).

To prevent the rollback, Omni should delete the META key with value:

https://github.com/siderolabs/talos/blob/2058bc992dea117babbbc22bce9fd729bbf9934c/internal/pkg/meta/constants.go#L8-L10