build,workflows: add a workflow to build and push builder image

[healthy-pod]

Release note: None
Epic: none

[cockroach-teamcity]

This change is 

[healthy-pod]

@jlinder The following needs to be addressed before this PR is merged:

• Update the workflows to be triggered manually using workflow_dispatch
• Merge the access PR in crl-infrastructure and update the uses of the images from DockerHub ones to GAR
• Keep using the existing TeamCity job to build and push the FIPS image but update the docs to use regctl image copy locally to copy the FIPS image from DockerHub to GAR and use the GAR one in CI

[jlinder]

Thank you for noting the remaining steps @healthy-pod. ❤️

[cockroach-teamcity]

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