docs: update pr template

Signed-off-by: Wanjin Noh <[email protected]>

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,9 +1,8 @@
-### To Reviewers
+### Skip Review (optional)
 - [ ] Minor change, self-reviewed (`style`, `chore`, `ci`, `test`, `docs`)
 - [ ] Previously reviewed in feature branch, no further review needed
 - [ ] Self-merge allowed for solo developers or urgent changes 
 
 ### Description (optional)
 
-
 ### Things to Talk About (optional)