reduced header size

.github/PULL_REQUEST_TEMPLATE/pull_request_template.md

@@ -1,11 +1,12 @@
-# Fixes #.
+## Fixes #.
 
-## Description of the changes:
+
+### Description of the changes:
 -
 -
 -
 
-## How changes were validated:
+### How changes were validated:
 <!--Review https://github.com/Microsoft/calculator/blob/master/CONTRIBUTING.md and ensure all contributing requirements are met.
 
 Specify how you tested your changes (i.e. manual/ad-hoc testing, automated testing, new automated tests added)-->