Revert "chore: update migrate and seed Job image tags during UAT promotion" image update for seed

The hardcoded image update for seedJob conflicts with Kustomize images transformer
override. Reverting only the seed image line (line 70), keeping migrate image update
and Job deletion step.

Root cause: Kustomize images transformer correctly overrides ghcr.io/groombook/seed
when newTag is set in UAT overlay. Overwriting the container[0].image directly in
the workflow causes the old tag (2026.04.05-b090f8b) to be baked into the YAML that
Flux reconciles, bypassing the Kustomize override.

Fix: groombook/groombook#247

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.github/workflows/promote-to-uat.yml

@@ -67,7 +67,6 @@ jobs:
           if [ -f "$SEED_JOB" ]; then
             yq -i '.metadata.name = "seed-test-data-" + env(SHORT_SHA)' "$SEED_JOB"
             yq -i '.metadata.annotations."groombook.app/deploy-version" = env(TAG)' "$SEED_JOB"
-            yq -i '.spec.template.spec.containers[0].image = "ghcr.io/groombook/seed:" + env(TAG)' "$SEED_JOB"
           fi
 
           git -C /tmp/infra diff --stat