docs(pull_request_template): add API Impact section (#4757)

.github/pull_request_template.md

@@ -33,10 +33,27 @@ Please check [x] relevant options, delete irrelevant ones.
 - [ ] New feature (non-breaking change which adds functionality)
 - [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
 - [ ] Refactor (non-breaking change that only restructures code)
-- [ ] Tests (You added tests for code that already exists, or your new feature included in this PR)
-- [ ] Documentation Updates
+- [ ] Tests (you added tests for code that already exists, or your new feature included in this PR)
+- [ ] Documentation update
+- [ ] Chore (no impact to binary, e.g. `.gitignore`, formatting, dropping support for older tooling)
 - [ ] Release
 
+### API Impact
+
+<!--
+Please check [x] relevant options, delete irrelevant ones.
+
+* If there is any impact to the public API methods (HTTP / WebSocket), please update https://github.com/xrplf/rippled/blob/develop/API-CHANGELOG.md
+  * Update API-CHANGELOG.md and add the change directly in this PR by pushing to your PR branch.
+* libxrpl: See https://github.com/XRPLF/rippled/blob/develop/docs/build/depend.md
+* Peer Protocol: See https://xrpl.org/peer-protocol.html
+-->
+
+- [ ] Public API: New feature (new methods and/or new fields)
+- [ ] Public API: Breaking change (in general, breaking changes should only impact the next api_version)
+- [ ] `libxrpl` change (any change that may affect `libxrpl` or dependents of `libxrpl`)
+- [ ] Peer protocol change (must be backward compatible or bump the peer protocol version)
+
 <!--
 ## Before / After
 If relevant, use this section for an English description of the change at a technical level.