Remove archived dependency on github.com/pkg/errors

[djdongjin]

Is your feature request related to a problem? Please describe.

The dependency repo (https://github.com/pkg/errors) has been archived and the functionality it provides is implemented in builtin errors pkg.

Describe the solution you'd like

Remove this dependency and use builtin errors pkg directly.

https://github.com/search?q=repo%3Aawslabs%2Fsoci-snapshotter%20%22github.51.al%2Fpkg%2Ferrors%22&type=code

Additional context

Similar issue in containerd repo: containerd/containerd#7940

Sample PR to remove the dependency: containerd/btrfs#35

[Kern--]

Please take note of wherever we're using errors.Is following this change and double check that there is test coverage for that branching. If not, please file additional issues.

[djdongjin]

Please take note of wherever we're using errors.Is following this change and double check that there is test coverage for that branching. If not, please file additional issues.

Created #326 which has a summary of errors.Is usage and test coverage.