Update PULL_REQUEST_TEMPLATE.md

.github/PULL_REQUEST_TEMPLATE.md

@@ -8,6 +8,7 @@ Please check the type of change your PR introduces:
 
 - [ ] Bugfix
 - [ ] Feature
+- [ ] UI change (please include screenshot!)
 - [ ] Code style update (formatting, renaming)
 - [ ] Refactoring (no functional changes, no api changes)
 - [ ] Build related changes
@@ -39,4 +40,4 @@ Before creating this PR, have you:
 
 - [ ] Followed the code style guideline as described in [CONTRIBUTING.md](https://github.com/veler/DevToys/blob/main/CONTRIBUTING.md)
 - [ ] Verified that the change work in Release build configuration
-- [ ] Checked all unit tests pass
+- [ ] Checked all unit tests pass