e2e: remove GCR

[crazy-max]

relates to https://github.com/docker/build-push-action/actions/runs/15042134376/job/42276145265#step:11:397

#40 exporting to image
#40 pushing layers 1.3s done
#40 ERROR: failed to push gcr.io/sandbox-298914/test-docker-action:gh-runid-15042134376: failed to authorize: failed to fetch oauth token: unexpected status from GET request to https://gcr.io/v2/token?scope=repository%3Asandbox-298914%2Ftest-docker-action%3Apull%2Cpush&service=gcr.io: 412 Precondition Failed

GCR was sunset on March 18, 2025: https://cloud.google.com/artifact-registry/docs/transition/transition-from-gcr

Container Registry is deprecated. Effective March 18, 2025, Container Registry is shut down and writing images to Container Registry is unavailable.