Add a high-level override to prevent Helix tests from running

azure-pipelines.yml

@@ -14,6 +14,11 @@ variables:
   _PublishUsingPipelines: true
   _DotNetArtifactsCategory: WINDOWSDESKTOP
 
+# This is set in the pipeline directly 
+# When set to false, CI tests will not be enabled in builds. 
+#
+# _ContinuousIntegrationTestsEnabled: true
+
 # Setting batch to true, triggers one build at a time.
 # if there is a push while a build in progress, it will wait,
 # until the running build finishes, and produce a build with all the changes

eng/pipeline.yml

@@ -157,4 +157,4 @@ jobs:
           HelixAccessToken: $(_HelixToken)              # only defined for internal CI
           Creator: $(_HelixCreator)
           SYSTEM_ACCESSTOKEN: $(System.AccessToken)
-        condition: and(succeeded(), eq(variables['_BuildConfig'], 'Release'), eq(variables['_HelixPublicBuildPipeline'], 'true')) # on helix machine (with real signing) when running on the public build pipeline
+        condition: and(succeeded(), eq(variables['_BuildConfig'], 'Release'), eq(variables['_HelixPublicBuildPipeline'], 'true'), ne(variables['_ContinuousIntegrationTestsEnabled'], 'false')) # on helix machine (with real signing) when running on the public build pipeline