docker: push ephemeral image to ttl.sh for pull requests (#6981)

[skip ci]

.github/workflows/docker.yml

@@ -81,7 +81,7 @@ jobs:
             View the job run at: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
 
   buildx-pull-request:
-    if: ${{ github.event_name == 'pull_request' && github.repository == 'gogs/gogs' }}
+    if: ${{ github.event_name == 'pull_request'}}
     runs-on: ubuntu-latest
     permissions:
       contents: read
@@ -102,11 +102,6 @@ jobs:
           echo "Status:    ${{ steps.buildx.outputs.status }}"
           echo "Flags:     ${{ steps.buildx.outputs.flags }}"
           echo "Platforms: ${{ steps.buildx.outputs.platforms }}"
-      - name: Login to Docker Hub
-        uses: docker/login-action@v1
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
       - name: Compute short commit SHA
         uses: benjlevesque/short-sha@v1.2
       - name: Build and push images
@@ -116,35 +111,7 @@ jobs:
           platforms: linux/amd64
           push: true
           tags: |
-            gogs/gogs:commit-${{ env.SHA }}
-
-  buildx-pull-request-fork:
-    if: ${{ github.event_name == 'pull_request' && github.repository != 'gogs/gogs' }}
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-      - name: Set up Docker Buildx
-        id: buildx
-        uses: docker/setup-buildx-action@v1
-        with:
-          config-inline: |
-            [worker.oci]
-              max-parallelism = 2
-      - name: Inspect builder
-        run: |
-          echo "Name:      ${{ steps.buildx.outputs.name }}"
-          echo "Endpoint:  ${{ steps.buildx.outputs.endpoint }}"
-          echo "Status:    ${{ steps.buildx.outputs.status }}"
-          echo "Flags:     ${{ steps.buildx.outputs.flags }}"
-          echo "Platforms: ${{ steps.buildx.outputs.platforms }}"
-      - name: Build images
-        uses: docker/build-push-action@v2
-        with:
-          context: .
-          platforms: linux/amd64
+            ttl.sh/gogs/gogs-${{ env.SHA }}:1d
 
   # Updates to the following section needs to be synced to all release branches within their lifecycles.
   buildx-release: