Upgrade deprecated CI actions versions

[janbrasna]

Description

Currently most GHA external actions are only specified as a major version. That helps keeping running up to date minor & patch updates, but such automagic support stops once they move to a new major release and cease maintaining the now obsolete branches we specify.

With upcoming Node 20 deprecation for actions a lot of key third party logins and setups will release new major versions that'll need upgrading to in Q2:

• https://github.com/docker/login-action/releases
• https://github.com/docker/setup-buildx-action/releases
• https://github.com/docker/build-push-action/releases

(expecting similar releases for gcloud setup et al.)

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Success Criteria

• No annotations for deprecated Node 20 actions
• Moving to current supported version branches