Merge pull request 'Only run CI on pushes to main and PRs' (#13) from woodpecker-run-only-on-main-and-pr into main

Reviewed-on: #13

.woodpecker.yaml

@@ -1,5 +1,9 @@
 steps:
   - name: lint
+    when:
+      - event: pull_request
+      - event: push
+        branch: main
     image: python:3-alpine
     commands:
       - python -m pip install --upgrade pip