Merge pull request dotnet#10940 from dotnet/target-branch-16.9

[release/dev16.9] update target insertion branch

Author: KevinRansom

azure-pipelines.yml

@@ -498,6 +498,6 @@ stages:
   - template: eng/release/insert-into-vs.yml
     parameters:
       componentBranchName: refs/heads/release/dev16.9
-      insertTargetBranch: main
+      insertTargetBranch: rel/d16.9
       insertTeamEmail: [email protected]
       insertTeamName: 'F#'