Address review comment: rename bot git username

Signed-off-by: Karthik Vetrivel <[email protected]>

Author: karthikvetrivel

.github/workflows/main.yml

@@ -88,7 +88,7 @@ jobs:
 
       - name: Configure git
         run: |
-          git config user.name "nvidia-bot"
+          git config user.name "nvidia-backport-bot"
           git config user.email "[email protected]"
 
       - name: Backport to release branches