fix(ci): remove Docker Hub from docker workflow

Author: echobt

.github/workflows/docker.yml

@@ -10,8 +10,6 @@ on:
 
 env:
   REGISTRY_GHCR: ghcr.io
-  REGISTRY_DOCKERHUB: docker.io
-  IMAGE_NAME: ${{ secrets.DOCKER_HUB_USERNAME || 'swe-forge' }}/swe-forge
 
 jobs:
   build:
@@ -34,21 +32,12 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Log in to Docker Hub
-        if: ${{ secrets.DOCKER_HUB_USERNAME != '' && secrets.DOCKER_HUB_TOKEN != '' }}
-        uses: docker/login-action@v3
-        with:
-          registry: ${{ env.REGISTRY_DOCKERHUB }}
-          username: ${{ secrets.DOCKER_HUB_USERNAME }}
-          password: ${{ secrets.DOCKER_HUB_TOKEN }}
-
       - name: Extract metadata for Docker
         id: meta
         uses: docker/metadata-action@v5
         with:
           images: |
             ${{ env.REGISTRY_GHCR }}/${{ github.repository }}
-            ${{ env.REGISTRY_DOCKERHUB }}/${{ env.IMAGE_NAME }}
           tags: |
             type=ref,event=branch
             type=ref,event=pr