pkg/auth: remove CRI Alpha API

[thaJeztah]

• relates to Remove CRI Alpha API stargz-snapshotter#1175

CRI v1alpha2 is deprecated since containerd 1.7:
https://github.com/containerd/containerd/blob/v1.7.0/RELEASES.md#deprecated-features

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 34.31%. Comparing base (261dd69) to head (f46b631).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #611      +/-   ##
==========================================
- Coverage   34.36%   34.31%   -0.05%     
==========================================
  Files          65       65              
  Lines        6606     6598       -8     
==========================================
- Hits         2270     2264       -6     
+ Misses       4021     4020       -1     
+ Partials      315      314       -1     

Files	Coverage Δ
pkg/auth/image_proxy.go	75.51% <100.00%> (+0.07%)	⬆️

[thaJeztah]

@imeoer rebased, and I included some of the fixes from @apostasie (from #604) in this patch, adding them as co-author.

My goal with these sets of PRs was to see if we could have a release with the new modules in place (removing the ones deprecated in containerd) before this module moves to v2, so that I can update the version used in BuildKit in preparation of dependencies starting to move to containerd v2 (these module moves in containerd are intended to help with that transition to make sure a common module is used between v1 and v2 codebases).

⚠️ Given that this PR removes some functionality, perhaps it warrants a v0.14.0
❓ maybe tagging current main / #610 as v0.13.15 ?

[imeoer]

cc @changweige

[thaJeztah]

FWIW: I opened a draft PR to test current main branch to verify it all works ok in BuildKit in case doing a v0.13.15 from current main is an option;

• [wip] vendor: github.com/containerd/nydus-snapshotter v0.13.15 moby/buildkit#5205

[imeoer]

LGTM!

[imeoer]

v0.14.0 released, thanks! cc @thaJeztah @apostasie