try fix MacOS CI error with XCode version 10.0

azure-pipelines.yml

@@ -10,7 +10,7 @@ variables:
 
   # Xcode Version overview: https://gist.github.com/yamaya/2924292
   # available versions: https://github.com/Microsoft/azure-pipelines-image-generation/blob/master/images/macos/macos-10.14-Readme.md
-  XCODE_VERSION: 10.2
+  XCODE_VERSION: 10.0
 
 jobs:
   # Todo - run Linux build in a container with a more recent Ubuntu version, maybe also try CentOS and Arch builds?