change URL to support landing page

.github/ISSUE_TEMPLATE/config.yml

@@ -10,5 +10,5 @@ contact_links:
       url: https://github.com/kimai/kimai/discussions
       about: Want to discuss something with a community? Do it in discussions!
     - name: Get Professional support
-      url: https://www.kimai.org/store/custom-plugins.html
+      url: https://www.kimai.org/en/support.html
       about: As a customer, you will always receive fast and helpful replies from the developer.