add ci pipeline

.gitea/workflows/ci.yaml

@@ -0,0 +1,27 @@
+name: ci
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: environment
+        run: |
+          echo "arch: $(uname -m)"
+          echo "runner works"
+
+      - name: run tests
+        run: |
+          python3 -c "assert 2 + 2 == 4; print('test passed')"
+
+      - name: build a docker image
+        run: |
+          cat > Dockerfile <<'DOCKER'
+          FROM alpine:latest
+          RUN echo "built on $(uname -m)" > /where
+          CMD cat /where
+          DOCKER
+          docker build -t ci-demo:${GITHUB_SHA::7} .
+          docker run --rm ci-demo:${GITHUB_SHA::7}