fix(ci): cd into overlay dir before kustomize edit set image

CTO review feedback: kustomize edit set image operates on the
kustomization.yaml in the current working directory. Since the
target file is at infra/apps/overlays/dev/kustomization.yaml, the
step must cd there before running kustomize.

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

.github/workflows/ci.yml

@@ -137,7 +137,7 @@ jobs:
 
       - name: Update dev overlay image tag
         run: |
-          cd infra
+          cd infra/apps/overlays/dev
           kustomize edit set image ghcr.io/cartsnitch/cartsnitch:${{ needs.build-and-push.outputs.calver_tag }}
 
       - name: Commit and push to infra