Cherrypick branch fix to prerelease branch

Author: dibarbet

azure-pipelines-official.yml

@@ -7,8 +7,10 @@ trigger:
 pr: none
 
 variables:
-  - name: prereleaseFlag
-    value: ''
+  ${{ if eq(variables['Build.SourceBranchName'], 'release') }}:
+    prereleaseFlag: ''
+  ${{ else }}:
+    prereleaseFlag: '--prerelease'
 
 stages:
 - stage: Build

azure-pipelines.yml

@@ -14,8 +14,10 @@ pr:
 - main
 
 variables:
-  - name: prereleaseFlag
-    value: ''
+  ${{ if eq(variables['Build.SourceBranchName'], 'release') }}:
+    prereleaseFlag: ''
+  ${{ else }}:
+    prereleaseFlag: '--prerelease'
 
 stages:
 - stage: Build