ci: 移除DockerHub登录和镜像推送的条件限制

之前DockerHub登录和镜像推送仅在`main`分支上执行，现移除条件限制，使所有分支都能推送镜像。这有助于在开发分支上测试和验证镜像构建流程。

.github/workflows/build-image.yml

@@ -57,7 +57,6 @@ jobs:
         uses: docker/setup-buildx-action@v3
 
       - name: Login to DockerHub
-        if: github.ref == 'refs/heads/main'
         uses: docker/login-action@v3
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
@@ -67,7 +66,7 @@ jobs:
         uses: docker/build-push-action@v6
         with:
           context: .
-          push: github.ref == 'refs/heads/main'
+          push: true
           platforms: ${{ env.PLATFORMS }}
           tags: ${{ steps.prep.outputs.tags }}
           cache-from: type=gha,scope=${{ env.DOCKER_IMAGE_NAME }}