Update worker version to 1.1.9

Author: Hanzhang Zeng (Roger)

setup.py

@@ -259,7 +259,7 @@ def run(self):
 
 setup(
     name='azure-functions-worker',
-    version='1.1.7',
+    version='1.1.9',
     description='Python Language Worker for Azure Functions Host',
     author="Microsoft Corp.",
     author_email="azurefunctions@microsoft.com",