blockscout/PULL_REQUEST_TEMPLATE.md

*[GitHub keywords to close any associated issues](https://blog.github.com/2013-05-14-closing-issues-via-pull-requests/)*

## Motivation

*Why should we merge these changes.  If using GitHub keywords to close [issues](https://github.com/poanetwork/blockscout/issues), this is optional as the motivation can be read on the issue page.*

## Changelog

### Enhancements
*Things you added that don't break anything.  Regression tests for Bug Fixes count as Enhancements.*

### Bug Fixes
*Things you changed that fix bugs.  If a fixes a bug, but in so doing adds a new requirement, removes code, or requires a database reset and reindex, the breaking part of the change should be added to Incompatible Changes below also.*

### Incompatible Changes
*Things you broke while doing Enhancements and Bug Fixes.  Breaking changes include (1) adding new requirements and (2) removing code.  Renaming counts as (2) because a rename is a removal followed by an add.*

## Upgrading

*If you have any Incompatible Changes in the above Changelog, outline how users of prior versions can upgrade once this PR lands or when reviewers are testing locally.  A common upgrading step is "Database reset and re-index required".*

## Checklist for your PR

<!--
  Ideally a PR has all of the checkmarks set.

  If something in this list is irrelevant to your PR, you should still set this
  checkmark indicating that you are sure it is dealt with (be that by irrelevance).

  If you don't set a checkmark (e. g. don't add a test for new functionality),
  you must be able to justify that.
-->

  - [ ] I added an entry to `CHANGELOG.md` with this PR
  - [ ] If I added new functionality, I added tests covering it.
  - [ ] If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.
  - [ ] I checked whether I should update the docs and did so if necessary
  - [ ] If I added/changed/removed ENV var, I should update the list of env vars in https://github.com/poanetwork/blockscout/blob/master/docs/env-variables.md to reflect changes in the table here https://poanetwork.github.io/blockscout/#/env-variables?id=blockscout-env-variables. I've set `master` in the `Version` column.
  - [ ] If I add new indices into DB, I checked, that they don't redundant with PGHero or other tools