Update PULL_REQUEST_TEMPLATE.md

Author: Lu-David

.github/PULL_REQUEST_TEMPLATE.md

@@ -3,5 +3,8 @@
 **Description of changes:**
 
 **How you tested your changes:**
+Environment (Linux / Windows): 
+Kubernetes Version: 
+
 
 By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.