fix(ci): remove GHA cache-from/cache-to (CAR-1357)

The build-and-push job fails post-merge of CAR-1356 REGISTRY_TOKEN fix:
cache-from/cache-to: type=gha backend does not exist on Gitea. Build
succeeds but post-build cache export fails and cascades to skipping the
Push Docker image step. Confirmed in uat run 3444 + dev run 3445.

Per CAR-1362, drop cache-from and cache-to from both Build and Push
Docker image steps. Matches proven-green cartsnitch/auth/ci.yml pattern.

Refs: CAR-1362, CAR-1356, CAR-1330, CAR-1357.

Co-authored-by: Paperclip <noreply@paperclip.ing>

.gitea/workflows/ci.yml

@@ -118,7 +118,7 @@ jobs:
           echo "CalVer tag: $VERSION"
 
       - name: Log in to Gitea Container Registry
-        run: echo "${{ github.token }}" | docker login git.farh.net -u ${{ github.actor }} --password-stdin
+        run: echo "${{ secrets.REGISTRY_TOKEN }}" | docker login git.farh.net -u ${{ github.actor }} --password-stdin
 
       - name: Extract metadata
         id: meta
@@ -140,8 +140,6 @@ jobs:
           labels: ${{ steps.meta.outputs.labels }}
           build-args: |
             APT_CACHE_BUST=${{ github.run_id }}
-          cache-from: type=gha
-          cache-to: type=gha,mode=max
 
       - name: Scan api image for vulnerabilities
         uses: anchore/scan-action@v5
@@ -168,7 +166,6 @@ jobs:
           labels: ${{ steps.meta.outputs.labels }}
           build-args: |
             APT_CACHE_BUST=${{ github.run_id }}
-          cache-from: type=gha
 
       - name: Create git tag
         if: github.event_name == 'push' && github.ref == 'refs/heads/main'