Automatically update changelog

Author: adangel

.github/workflows/check-changelog.yml

@@ -1,5 +1,6 @@
 # CHANGELOG.md is generated by https://github.com/github-changelog-generator/github-changelog-generator
 # This job verifies, that it contains always the current content
+# and also pushes the updated changelog to https://github.com/pmd/pmd-github-action/blob/main/CHANGELOG.md
 name: Check Changelog
 
 on:
@@ -30,13 +31,22 @@ jobs:
           if [ "$(git diff CHANGELOG.md | wc -l)" -gt "0" ]; then
             echo "Detected uncommitted changes after build.  See status below:"
             git diff
-            exit 1
+            echo "changelog=outdated" >> $GITHUB_ENV
+          else
+            echo "changelog=current" >> $GITHUB_ENV
           fi
         id: diff
 
       # If CHANGELOG.md was different than expected, upload the expected version as an artifact
       - uses: actions/upload-artifact@v2
-        if: ${{ failure() && steps.diff.conclusion == 'failure' }}
+        if: ${{ env.changelog == 'outdated' }}
         with:
           name: changelog
           path: CHANGELOG.md
+
+      - name: Push changes to CHANGELOG.md
+        if: ${{ github.repository == 'pmd/pmd-github-action' && env.changelog == 'outdated' }}
+        run: |
+          git config --local user.email "<>"
+          git config --local user.name "GitHub Actions Bot"
+          git add CHANGELOG.md && git commit -m 'Updated CHANGELOG.md' && git push origin main

.github_changelog_generator

@@ -1,3 +1,5 @@
 user=pmd
 project=pmd-github-action
 include-tags-regex=v\d{1,}\.\d{1,}\.\d{1,}
+add-sections={"dependencies":{"prefix":"**Dependency updates:**","labels":["dependencies"]}}
+usernames-as-github-logins=true