Author: Luca Boccassi <bluca@debian.org>
Description: do not add None to sys.path
 many libraries break, causing build/test failures
Forwarded: https://github.com/Azure/azure-devops-cli-extension/pull/1030
--- a/azure-devops/azext_devops/test/conftest.py
+++ b/azure-devops/azext_devops/test/conftest.py
@@ -9,4 +9,6 @@
 # Make sure that the extension install directory is on sys.path so that dependencies can be found.
 
 extensionPath = get_extension_path('azure-devops')
-sys.path.append(extensionPath)
+# Adding None to sys.path breaks numerous libraries, including pkg_resources
+if extensionPath is not None:
+    sys.path.append(extensionPath)