Use dynamic onebranch template

Author: adityapatwardhan

.pipelines/release.yml

@@ -23,7 +23,7 @@ resources:
     ref: refs/heads/main
 
 extends:
-  template: v2/OneBranch.NonOfficial.CrossPlat.yml@templates  # The Official template may only be used by Production-classified pipelines
+  template: $(templateFile)  # The Official template may only be used by Production-classified pipelines
 
   parameters:
     release: