update template instructions for integration tests (#765)

Co-authored-by: kcadette <[email protected]>

Author: awsdrbalaji

.github/PULL_REQUEST_TEMPLATE.md

@@ -9,5 +9,7 @@ Checklist:
 
 * [ ] Have you successfully deployed to an AWS account with your changes?
 * [ ] Have you written new tests for your core changes, as applicable?
+* [ ] Did you add new integration tests?
+* [ ] Did you run integration tests with your changes?
 
 By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.