Comment out notes in pull request template

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,11 +2,11 @@
 
 Proposed change:
 
-{{
+<!--
 	Please replace this with a human-friendly description of your proposed change.
 	* If you have multiple changes, try to split them into separate PRs.
 	* If this change closes an issue, please write "Closes #{number}".
-}}
+-->
 
 Closes # .
 
@@ -20,4 +20,4 @@ I've completed the checklist below to ensure I didn't forget anything. This make
 * [ ] [*Tests*](https://github.com/mozilla/nunjucks/tree/master/tests) are added / updated to cover proposed change.
 * [ ] [*Changelog*](https://github.com/mozilla/nunjucks/blob/master/CHANGELOG.md) has an entry for proposed change (if user-facing fix or feature).
 
-(Tick of items by replacing `[ ]` by `[x]`)
+<!-- Tick of items by replacing `[ ]` by `[x]` -->