[codex] Remove stale changelog PR template instruction

[szdziedzic]

Why

The PR template tells contributors to add changelog entries by commenting with /changelog-entry ..., but the repository changelog workflow only checks whether CHANGELOG.md changed on pull request events. There is no issue_comment workflow handling that slash command, so the instruction points contributors at a no-op path.

#3982 (comment)

How

Removed the stale /changelog-entry instruction from .github/PULL_REQUEST_TEMPLATE. The rest of the template remains intact, including the guidance for using the no changelog label when a changelog entry is not required.

Test Plan

• git diff --check
• ./node_modules/.bin/oxfmt .

[github-actions]

⏩ The changelog entry check has been skipped since the "no changelog" label is present.

[github-actions]

Subscribed to pull request

File Patterns	Mentions
**/*	@douglowder

Generated by CodeMention

Warning: The preamble and epilogue options in commentConfiguration are deprecated. Use template instead.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.34%. Comparing base (081e1a9) to head (6b41d41).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3984      +/-   ##
==========================================
+ Coverage   59.33%   59.34%   +0.02%     
==========================================
  Files         936      936              
  Lines       41172    41186      +14     
  Branches     8671     8675       +4     
==========================================
+ Hits        24424    24438      +14     
  Misses      16654    16654              
  Partials       94       94              

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