Configure gsoci.azurecr.io as the registry to use by default

[marians]

Towards

• Modify app values to replace docker.io as container registry domain with gsoci.azurecr.io roadmap#3017

This PR replaces any occurrence of docker.io in values.yaml files with gsoci.azurecr.io,
to make the new ACR registry the default one.

[marians]

@giantswarm/team-shield In this case I wasn't really sure which images can be pulled from gsoci.azurecr.io and which ones have to come from docker.io. I only changed the ones that have the giantswarm/ namespace prefix.

[Strigix]

The upstream charts don't need their image set, this will be overwritten by our app-level values.yaml.

[marians]

Thanks @Strigix ! Will there be a release any time soon, or should I trigger one?

[Strigix]

I'll do a quick test to see if it pulls like it should, if yes. I'll release a patch today 🥳