Keep Flutter workflow registry-auth neutral

.gitea/workflows/build-and-deploy.yml

@@ -19,25 +19,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Login to registry
-        env:
-          REGISTRY_USERNAME: ${{ secrets.REGISTRY_USERNAME }}
-          REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
-          GITEA_ACTOR: ${{ github.actor }}
-          GITEA_TOKEN: ${{ github.token }}
-        run: |
-          set -euo pipefail
-          if [ -n "${GITEA_TOKEN:-}" ]; then
-            if printf '%s' "$GITEA_TOKEN" | docker login gitea.dsrptlab.com -u "$GITEA_ACTOR" --password-stdin; then
-              exit 0
-            fi
-          fi
-          username="${REGISTRY_USERNAME:-$GITEA_ACTOR}"
-          token="${REGISTRY_TOKEN:-}"
-          test -n "$username"
-          test -n "$token"
-          printf '%s' "$token" | docker login gitea.dsrptlab.com -u "$username" --password-stdin
-
       - name: Build and push image
         run: |
           set -euo pipefail