feat: Setup Stale workflow (#524)

* feat: Setup Stale workflow

* Change stale pull request message

Thanks, @Thomas-Boi!

* Add a note on `README.md` about stale PRs

* Fix some issues with the workflow

* Apply suggestions from code review

Co-authored-by: Clemens Bastian <amacado@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Clemens Bastian <amacado@users.noreply.github.com>

Co-authored-by: Clemens Bastian <amacado@users.noreply.github.com>

.github/workflows/stale.yml

@@ -0,0 +1,22 @@
+name: 'Stale'
+on:
+  schedule:
+    - cron: '30 1 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@main
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          stale-pr-message: 'Hello there,
+          we noticed that this PR has been inactive for a while now. If there are any changes which are suitable for our repository,
+          we would love to have it. It would be great if you can continue with this PR, but if you cannot, we might fork your changes and merge the changes ourselves.
+
+          Since GitHub tracks contributions by commits, you will still be credited.
+
+          Let us know what you think 😃'
+        stale-pr-label: 'stale'
+        days-before-pr-stale: 30
+        days-before-pr-close: -1

README.md

@@ -51,6 +51,7 @@
     <li><a href="#getting-started">Getting started</a></li>
     <li><a href="#request-icon">Requesting icon</a></li>
     <li><a href="#contribute">Contributing</a></li>
+    <li><a href="#stale-prs">Stale pull requests</a></li>
     <li><a href="#build-yourself">Go build yourself</a></li>
 </ol>
 
@@ -155,6 +156,11 @@ Add css rules in your stylesheet
     to see how you can contribute to this project.
 </p>
 
+<h2 id="stale-prs">Stale pull requests</h2>
+<p>
+After a pull request has been open for over 30 days with no activity or response from the author, it'll be automatically marked as stale. We might fork your changes and merge the changes ourselves. Since GitHub tracks contributions by commits, you will be credited.
+</p>
+
 <h2 id="build-yourself">Go build yourself</h2>
 <p>
     Feel free to follow those steps when you want to build the font