ci: 修正runs-on标签与镜像默认名, 增加workflow_dispatch

.gitea/workflows/docker-push.yml

@@ -6,7 +6,7 @@ on:
   workflow_dispatch:
 jobs:
   build-and-push:
-    runs-on: [self-hosted, Nexus]
+    runs-on: Nexus
     steps:
       - uses: actions/checkout@v4
       - uses: docker/setup-buildx-action@v3
@@ -29,12 +29,15 @@ jobs:
             ${{ env.IMAGE }}:latest
             ${{ env.IMAGE }}:${{ env.SHA }}
   deploy:
-    runs-on: [self-hosted, Nexus]
+    runs-on: Nexus
     needs: build-and-push
     steps:
       - uses: actions/checkout@v4
       - name: Set image ref
-        run: echo "IMAGE_REF=${{ secrets.REGISTRY }}/${{ secrets.REGISTRY_NAMESPACE }}/${{ secrets.IMAGE_NAME || 'nexus-material' }}:latest" >> $GITHUB_ENV
+        run: |
+          IMG_NAME="${{ secrets.IMAGE_NAME }}"
+          if [ -z "$IMG_NAME" ]; then IMG_NAME="nexus-material"; fi
+          echo "IMAGE_REF=${{ secrets.REGISTRY }}/${{ secrets.REGISTRY_NAMESPACE }}/$IMG_NAME:latest" >> $GITHUB_ENV
       - name: Upload compose to server
         uses: appleboy/scp-action@v0.1.7
         with: