Github issues config: fix broken link

Since we deprecate mirror repository, issues can't be open for infra anymore

Author: igorpecovnik

.github/ISSUE_TEMPLATE/config.yml

@@ -19,5 +19,5 @@ contact_links:
     url: https://github.com/armbian/configng/issues/new
     about: Utility for configuring your board, adjusting services and installing applications.
   - name: Issue with infrastructure
-    url: https://github.com/armbian/mirror/issues/new
+    url: https://github.com/armbian/armbian-router/issues/new
     about: Broken download links or just slow download