[Improvement][docs] Fix typo in CONTRIBUTING.md (#3624)

Co-authored-by: 李庆忠 <liqingzhong@inspur.com>

CONTRIBUTING.md

@@ -56,7 +56,7 @@ If remote branch has a new branch `DEV-1.0`, you need to synchronize this branch
 
 ```
 git checkout -b dev-1.0 upstream/dev-1.0
-git push --set-upstream origin dev1.0
+git push --set-upstream origin dev-1.0
 ```
 
 ## Create your feature branch