Update pull_request_template.md

Author: animator

.github/pull_request_template.md

@@ -9,6 +9,7 @@ _Add your description_
 
 ### Checklist
 - [ ] I have gone through the [contributing guide](https://github.com/foss42/apidash/blob/main/CONTRIBUTING.md)
+- [ ] I have updated my branch and synced it with project `main` branch before making this PR
 - [ ] I have run the tests (`flutter test`) and all tests are passing
 
 ## Added/updated tests?