Add a gitea workflow

.gitea/workflows/test.yaml

@@ -0,0 +1,18 @@
+name: Testing
+on: [push]
+
+jobs:
+  default:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install dependencies
+        run: |
+          apt-get update
+          apt-get install -yq --no-install-suggests --no-install-recommends \
+          xauth xvfb
+      - name: Check out repository code
+        uses: actions/checkout@v3
+      - name: Install
+        run: npm install
+      - name: Run tests
+        run: npm test