fix(ci): use CI_GITEA_TOKEN for cross-repo checkout

Update deploy-dev and deploy-uat jobs to use CI_GITEA_TOKEN for
checking out the cartsnitch/infra repository instead of REGISTRY_TOKEN.

CI_GITEA_TOKEN is the org-level Actions secret configured for cross-repo
access, while REGISTRY_TOKEN continues to be used for Docker registry login.

This resolves CAR-986 by enabling CI to commit image tag updates to
the private infra repository.

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

.gitea/workflows/ci.yml

@@ -467,7 +467,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: cartsnitch/infra
-          token: ${{ secrets.REGISTRY_TOKEN }}
+          token: ${{ secrets.CI_GITEA_TOKEN }}
           ref: main
           path: infra
 
@@ -557,7 +557,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           repository: cartsnitch/infra
-          token: ${{ secrets.REGISTRY_TOKEN }}
+          token: ${{ secrets.CI_GITEA_TOKEN }}
           ref: main
           path: infra