retain .gdn files during auto sync

Author: gargsaumya

OneBranchPipelines/github-ado-sync.yml

@@ -66,8 +66,8 @@ jobs:
         git config user.name "ADO Sync Bot"
         
         git fetch github main
-        git rm -rf .
-        git checkout github/main -- .
+        git rm -rf . -- :!.gdn
+        git checkout github/main -- . :!.gdn
         echo timestamp.txt >> .git\info\exclude
         echo branchname.txt >> .git\info\exclude
         git diff --cached --quiet