Update docker/setup-buildx-action action to v4

.gitea/workflows/docker-build.yaml

@@ -1,10 +1,10 @@
-name: Docker build and push
+name: Docker Build and Push
 
 on:
   pull_request:
-    branches: [master]
+    branches: [main]
   push:
-    branches: [master]
+    branches: [main]
   schedule:
     - cron: '0 0 * * *'
 
@@ -16,7 +16,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Login to Docker Hub
         if: github.event_name != 'pull_request'
@@ -34,7 +34,7 @@ jobs:
             type=ref,event=branch
             type=ref,event=pr
             type=sha
-            type=raw,value=latest,enable=${{ github.ref == 'refs/heads/master' }}
+            type=raw,value=latest,enable=${{ github.ref == 'refs/heads/main' }}
 
       - name: Build and push
         uses: docker/build-push-action@v6