New script: check_dates

Author: MichaelRWolf

.github/workflows/ci.yml

@@ -57,6 +57,9 @@ jobs:
     # - name: Build site
     #   run: bundle exec jekyll build
 
+    - name: Check date consistency in _posts
+      run: bin/check_dates
+
     - name: Deploy to GitHub Pages
       uses: peaceiris/actions-gh-pages@v3
       with: