Add forgejo action CI

.forgejo/workflows/test.yml

@@ -0,0 +1,13 @@
+on:
+  push:
+    branches:
+      - "**"
+      - "!main"
+jobs:
+  docker-build-only:
+    runs-on: docker
+    steps:
+      - name: set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+        with:
+          driver: docker