Update PR template

Author: Rom1-B

.github/pull_request_template.md

@@ -4,6 +4,7 @@
 
 - [ ] I have performed a self-review of my code.
 - [ ] I have added tests (when available) that prove my fix is effective or that my feature works.
+- [ ] I have updated the CHANGELOG with a short functional description of the fix or new feature.
 - [ ] This change requires a documentation update.
 
 ## Description
@@ -12,4 +13,3 @@
 - Here is a brief description of what this PR does
 
 ## Screenshots (if appropriate):
-