Add missing 3.6.2 GitHub stats to release notes

Author: QuLogic

doc/users/release_notes.rst

@@ -18,6 +18,7 @@ Version 3.6
     ../api/prev_api_changes/api_changes_3.6.1.rst
     ../api/prev_api_changes/api_changes_3.6.0.rst
     github_stats.rst
+    prev_whats_new/github_stats_3.6.2.rst
     prev_whats_new/github_stats_3.6.1.rst
     prev_whats_new/github_stats_3.6.0.rst