chore: add prettier to checklist (#167)

Adding prettier to the checklist since formatting
is often forgotten and can result in issues with linting,
impeding cycle time to merge PRs.

Author: toumorokoshi

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,8 +1,8 @@
-## 📑 Proposed changes
-
+<!--
 Describe the big picture of your changes here to communicate to the maintainers
 why we should accept this pull request. If it fixes a bug or resolves a feature
 request, be sure to link to that issue.
+-->
 
 ## 🍱 Types of changes
 
@@ -12,6 +12,7 @@ that apply_
 - [ ] Enhancement
 - [ ] [New proposal](https://aep.dev/1#workflow)
 - [ ] Migrated from google.aip.dev
+- [ ] Chore / Quick Fix
 
 ## 📋 Your checklist for this pull request
 
@@ -24,9 +25,13 @@ contributing to this repository.
 - [ ] Ensure that your PR
       [references AEPs](https://aep.dev/style-guide#referencing-aeps)
       correctly.
+- [ ] [My code has been formatted](https://aep.dev/contributing#formatting)
+      (usually `prettier -w .`)
 
 ### Additional checklist for a new AEP
 
+<!-- delete if this is not a new AEP -->
+
 - [ ] A new AEP **should** be no more than two pages if printed out.
 - [ ] Ensure that the PR is editable by maintainers.
 - [ ] Ensure that [File structure](https://aep.dev/style-guide#file-structure)