Build: update PR template

- Comment out things we don't need to see in the PR description
- Change CLA link

.github/PULL_REQUEST_TEMPLATE.md

@@ -6,11 +6,15 @@ should start with an issue. Mention the issue number here.
 
 
 ### Checklist ###
+<!--
 Mark an `[x]` for completed items, if you're not sure leave them unchecked and we can assist.
+-->
 
-* [ ] All authors have signed the CLA at https://contribute.jquery.com/CLA/
+* [ ] All authors have signed the CLA at https://cla.js.foundation/jquery/jquery
 * [ ] New tests have been added to show the fix or feature works
 * [ ] Grunt build and unit tests pass locally with these changes
 * [ ] If needed, a docs issue/PR was created at https://github.com/jquery/api.jquery.com
 
+<!--
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