fix: auto comment actions

.github/workflows/comment-on-pr.yml

@@ -10,13 +10,13 @@ jobs:
   comment:
     runs-on: ubuntu-latest
     steps:
-      - if: github.event.issue.pull_request != ''
+      - if: github.event_name == 'pull_request'
         name: Comment on PR
         uses: github-actions-up-and-running/pr-comment@v1.0.1
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           message: "👍 感谢提交该 PR，请确保使用了 [PR 模板](https://github.com/DIYgod/RSSHub/blob/master/.github/PULL_REQUEST_TEMPLATEpull_request_template.md) 以便于测试。<br /><br />👍 Thanks for the PR, please make sure you have followed the [PR template](https://github.com/DIYgod/RSSHub/blob/master/.github/PULL_REQUEST_TEMPLATE/pull_request_template.md) to simplify the testing."
-      - if: github.event.issue.pull_request == ''
+      - if: github.event_name == 'issues'
         name: Comment on Issue
         uses: ben-z/actions-comment-on-issue@1.0.2
         with: