simplify the pr template (#411)

### Description

Template had too many sections which were never use. keep it simple.
keep it clean. keep it useful

<!-- start pr-codex -->

---

## PR-Codex overview
This PR updates the pull request template in the
`.github/pull_request_template.md` file to enhance clarity and
structure, particularly in the explanation of changes and their
implications.

### Detailed summary
- Changed the prompt from "A few sentences describing the overall
effects and goals..." to "Tell us why these changes are being made".
- Updated section header from "### Other changes" to "#### Other
changes".
- Added a note to delete the "Other changes" section if none exist.
- Removed the "### Backwards compatibility" and "### Documentation"
sections from the template.

> ✨ Ask PR-Codex anything about this PR by commenting with `/codex {your
question}`

<!-- end pr-codex -->

.github/pull_request_template.md

@@ -1,11 +1,10 @@
 ### Description
 
-_A few sentences describing the overall effects and goals of the pull request's commits.
-What is the current behavior, and what is the updated/expected behavior with this PR?_
+_Tell us why these changes are being made_
 
-### Other changes
+#### Other changes
 
-_Describe any minor or "drive-by" changes here._
+_Describe any minor or "drive-by" changes here. If none delete this section_
 
 ### Tested
 
@@ -14,11 +13,3 @@ _An explanation of how the changes were tested or an explanation as to why they
 ### Related issues
 
 - Fixes #[issue number here]
-
-### Backwards compatibility
-
-_Brief explanation of why these changes are/are not backwards compatible._
-
-### Documentation
-
-_The set of community facing docs that have been added/modified because of this change_