Merge pull request #21792 from Homebrew/pull_request_template

PULL_REQUEST_TEMPLATE: tweak and make consistent.

Author: MikeMcQuaid

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,7 +1,12 @@
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+
+<!-- Do not tick a checkbox if you haven’t performed its action. Honesty is indispensable for a smooth review process. -->
+<!-- Use [x] to mark item done before creation, or just click the checkboxes with device pointer after creation -->
+
 - [ ] Have you followed the guidelines in our [Contributing](https://github.com/Homebrew/brew/blob/HEAD/CONTRIBUTING.md) document?
 - [ ] Have you checked to ensure there aren't other open [Pull Requests](https://github.com/Homebrew/brew/pulls) for the same change?
 - [ ] Have you added an explanation of what your changes do and why you'd like us to include them?
-- [ ] Have you written new tests for your changes? [Here's an example](https://github.com/Homebrew/brew/blob/HEAD/Library/Homebrew/test/PATH_spec.rb).
+- [ ] Have you written new tests (excluding integration tests) for your changes? [Here's an example](https://github.com/Homebrew/brew/blob/HEAD/Library/Homebrew/test/PATH_spec.rb).
 - [ ] Have you successfully run `brew lgtm` (style, typechecking and tests) with your changes locally?
 
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