add rel/4.* into PR or CI trigger (#5019)

Author: HongGit

azure-pipelines-arcade.yml

@@ -8,13 +8,15 @@ trigger:
     include:
     - main
     - release/3.*
+    - rel/4.*
 
 # trigger ci builds for pull requests into listed branches
 pr:
   branches:
     include:
     - main
     - release/3.*
+    - rel/4.*
 
 variables:  
   - name: _TeamName