compose-jb/.github/PULL_REQUEST_TEMPLATE.md

Describe proposed changes and the issue being fixed

<!-- Optional -->
Fixes [link to the issue]

## Testing
<!-- Optional -->
Describe how you tested your changes. If possible and needed:
- Test it on a sample project
- Write unit tests
- Provide a code snippet

<!-- Optional -->
This should be tested by QA

## Release Notes
<!--
Optional, if omitted - won't be included in the changelog

Sections:
- Highlights
- Known Issues
- Breaking Changes
- Features
- Fixes

Subsections:
- Multiple Platforms
- iOS
- Desktop
- Web
- Android
- Resources
- Gradle Plugin
-->
### Section - Subsection
- Describe a change for adding it to https://github.com/JetBrains/compose-multiplatform/blob/master/CHANGELOG.md
- _(prerelease fix)_ Fix some bug that introduced in a prerelease version (dev/beta). It will be included in a dev/beta changelog, but excluded from a stable changelog

### Section - Subsection
- Describe another change if needed