.github/PULL_REQUEST_TEMPLATE

<!--
    ⚠️ Please make sure to read this template first, pull requests that don't accord with this template
    maybe closed without notice.
    Texts surrounded by `<` and `>` are meant to be replaced by you, e.g. <framework name>, <issue number>.
    Put an `x` in the `[ ]` to mark the item as CHECKED. `[x]`
-->

<!-- ==== 🐛 Remove this line WHEN AND ONLY WHEN you're fixing a bug, follow the checklist 👇 ====
### Fix <bug description or the bug issue number or bug issue link>
- [ ] Add a unit test to verify that the fix works.
- [ ] Explain briefly why the bug exists and how to fix it.
     ==== 🐛 Remove this line WHEN AND ONLY WHEN you're fixing a bug, follow the checklist 👆 ==== -->

<!-- ==== 📈 Remove this line WHEN AND ONLY WHEN you're improving the performance, follow the checklist 👇 ====
### Improve the performance of <class or module or ...>
- [ ] Add a benchmark for the improvement, refer to [the existing ones](https://github.com/apache/skywalking/blob/master/apm-commons/apm-datacarrier/src/test/java/org/apache/skywalking/apm/commons/datacarrier/LinkedArrayBenchmark.java)
- [ ] The benchmark result.
```text
<Paste the benchmark results here>
```
- [ ] Links/URLs to the theory proof or discussion articles/blogs. <links/URLs here>
     ==== 📈 Remove this line WHEN AND ONLY WHEN you're improving the performance, follow the checklist 👆 ==== -->

<!-- ==== 🆕 Remove this line WHEN AND ONLY WHEN you're adding a new feature, follow the checklist 👇 ====
### <Feature description>
- [ ] If this is non-trivial feature, paste the links/URLs to the design doc.
- [ ] Update the documentation to include this new feature.
- [ ] Tests(including UT, IT, E2E) are added to verify the new feature.
- [ ] If it's UI related, attach the screenshots below.
     ==== 🆕 Remove this line WHEN AND ONLY WHEN you're adding a new feature, follow the checklist 👆 ==== -->

- [ ] If this pull request closes/resolves/fixes an existing issue, replace the issue number. Closes #<issue number>.
- [ ] Update the [`CHANGES` log](https://github.com/apache/skywalking/blob/master/docs/en/changes/changes.md).