Add python helloworld to azure-pipelines-codeql.yml

To make sure codeql doesn't fail because it didn't process any python files.

Author: akoeplinger

eng/azure-pipelines-codeql.yml

@@ -66,6 +66,11 @@ stages:
         - task: CodeQL3000Init@0
           displayName: Initialize CodeQL (manually-injected)
 
+        - bash: |
+            echo 'print("Hello world")' > hello.py
+            python3 hello.py
+          displayName: 'Run python helloworld'
+
         - bash: |
             ./build.sh --ci --restore --build --pack $(archflag) --configuration $(_BuildConfig) $(_InternalBuildArgs) $(ClangBinDirArg) $(ClangTargetArg) $(ExtraArgs)
           displayName: 'Build and package'