add: リリース時にDockerイメージをpush

.github/workflows/on-release-publish-docker.yml

@@ -0,0 +1,35 @@
+name: On Release Created (Publish misskey-js)
+
+on:
+  release:
+    types: [created]
+  workflow_dispatch:
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+          - linux/amd64
+          - linux/arm64
+    if: github.repository == 'team-shahu/misskey'
+    steps:
+      - uses: actions/checkout@v3
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Build Docker Image
+        run: |
+          docker build --tag ghcr.io/${{ github.repository_owner }}/misskey:latest \
+          --tag ghcr.io/${{ github.repository_owner }}/misskey:${{ env.RELEASE_TAG }} \
+          .
+      - name: Push Docker Image
+        run: |
+          docker push ghcr.io/${{ github.repository_owner }}/misskey:latest
+          docker push ghcr.io/${{ github.repository_owner }}/misskey:${{ env.RELEASE_TAG }}