fix(#33711): cross-publish docker images to ghcr.io (#34148)

This PR will cross-publish the release, rc, and nightly images from
`docker.io` to `ghcr.io` as docker hub has imposed rate-limiting

Signed-off-by: Allen Conlon <software@conlon.dev>

.github/workflows/release-nightly.yml

@@ -59,6 +59,8 @@ jobs:
           aws s3 sync dist/release s3://${{ secrets.AWS_S3_BUCKET }}/gitea/${{ steps.clean_name.outputs.branch }} --no-progress
   nightly-docker-rootful:
     runs-on: namespace-profile-gitea-release-docker
+    permissions:
+      packages: write # to publish to ghcr.io
     steps:
       - uses: actions/checkout@v4
       # fetch all commits instead of only the last as some branches are long lived and could have many between versions
@@ -85,6 +87,12 @@ jobs:
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Login to GHCR using PAT
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: fetch go modules
         run: make vendor
       - name: build rootful docker image
@@ -93,9 +101,13 @@ jobs:
           context: .
           platforms: linux/amd64,linux/arm64
           push: true
-          tags: gitea/gitea:${{ steps.clean_name.outputs.branch }}
+          tags: |-
+            gitea/gitea:${{ steps.clean_name.outputs.branch }}
+            ghcr.io/go-gitea/gitea:${{ steps.clean_name.outputs.branch }}
   nightly-docker-rootless:
     runs-on: namespace-profile-gitea-release-docker
+    permissions:
+      packages: write # to publish to ghcr.io
     steps:
       - uses: actions/checkout@v4
       # fetch all commits instead of only the last as some branches are long lived and could have many between versions
@@ -122,6 +134,12 @@ jobs:
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Login to GHCR using PAT
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: fetch go modules
         run: make vendor
       - name: build rootless docker image
@@ -131,4 +149,6 @@ jobs:
           platforms: linux/amd64,linux/arm64
           push: true
           file: Dockerfile.rootless
-          tags: gitea/gitea:${{ steps.clean_name.outputs.branch }}-rootless
+          tags: |-
+            gitea/gitea:${{ steps.clean_name.outputs.branch }}-rootless
+            ghcr.io/go-gitea/gitea:${{ steps.clean_name.outputs.branch }}-rootless