ci: remove debug arm64 db workflow

.github/workflows/dev-db-arm64.yml

@@ -1,35 +0,0 @@
-name: Debug - Dev DB Image ARM64
-
-on:
-  workflow_dispatch:
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      packages: write
-    steps:
-      - uses: actions/checkout@v2
-        
-      - name: Set up QEMU
-        uses: docker/setup-qemu-action@v2
-
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v2
-
-      - name: Login to GitHub Container Registry
-        uses: docker/login-action@v2
-        with:
-          registry: ghcr.io
-          username: ${{ github.actor }}
-          password: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Docker Build & Push
-        uses: docker/build-push-action@v3
-        with:
-          context: .
-          file: docker/db.Dockerfile
-          platforms: linux/arm64
-          push: true
-          tags: ghcr.io/ietf-tools/datatracker-db-arm64:latest