added notice to PR template

.github/pull_request_template.md

@@ -5,6 +5,7 @@
 <!-- Enter the ticket number and link to the issue you are completing, if appropriate -->
 
 ## Checklist before requesting a review
+> The PR will only be considered when all items within the checklist are marked as complete. Feel free to submit an incomplete draft PR, and add additional commits until you are able to satisfy each item within the checklist.
 - [ ] I have performed a self-review of my code
 - [ ] I have submitted at most one additional endpoint implementation
 - [ ] I have either submitted no additional endpoint implementation, or my implementation covers both client and server SDK's, unless either are marked in the [README](https://github.com/PinguApps/AppwriteSdk/blob/dev/README.md) with a ❌