Allow configuring registry_patterns in oci_pull

[sfc-gh-mhazy]

Currently registry patterns are hardcoded here:

rules_oci/oci/private/authn.bzl

Line 9 in 9faf210

_WWW_AUTH = {

If one uses private registry, they can either add their pattern to this list (app.snowflake.com as an example), or apply patches in their workspaces.

I think the more flexible solution could be to allow passing the registry patterns in oci_pull.

I'm happy to add the change if you agree.

[shs96c]

Applying patches in a world where we rely on bzlmod isn't going to be appropriate or possible in all cases. Having a mechanism to add additional registry patterns that doesn't require us to patch rules_oci would be most useful.

[thesayyn]

I strongly agree with you both, there is #126.

I don't have the time to implement it myself, but if anybody is willing to put up a PR with some tests.