fix slack link

_data/navigation.yml

@@ -11,7 +11,7 @@ nav:
       - title: Code
         link: https://github.com/simbricks
       - title: Join our Slack
-        link: https://join.slack.com/t/simbricks/shared_invite/zt-16y96155y-xspnVcm18EUkbUHDcSVonA
+        link: /join-slack
   - title: About
     link: /about.html
   - title: Blog

_includes/footer.html

@@ -25,7 +25,7 @@
           <li><a href="https://twitter.com/sim_bricks" class="twitter" title="Twitter"></a></li>
           <li><a href="mailto:info@simbricks.io" class="email" title="Email"></a></li>
           <li><a href="https://www.linkedin.com/company/simbricks/" class="linkedin" title="LinkedIn"></a></li>
-          <li><a href="https://join.slack.com/t/simbricks/shared_invite/zt-16y96155y-xspnVcm18EUkbUHDcSVonA" class="slack" title="Slack"></a></li>
+          <li><a href="/join-slack" class="slack" title="Slack"></a></li>
         </ul>
       </nav>
       <div class="copyright">&copy; SimBricks, 2022&ndash;2024 &mdash;