**Description**
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  Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context.
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Ref #ISSUE

**Checklist:**
- [ ] I have followed [Pull Request guidelines](https://github.com/solidusio/solidus/blob/master/CONTRIBUTING.md#pull-request-guidelines)
- [ ] I have added a detailed description into each commit message
- [ ] I have updated Guides and README accordingly to this change (if needed)
- [ ] I have added tests to cover this change (if needed)
- [ ] I have added a CHANGELOG entry for this change (if needed)

**Description**
<!--
  Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context.

  If needed you can reference another PR or issue here, e.g.:
  Ref #ISSUE
-->

**Checklist:**
- [ ] I have followed [Pull Request guidelines](https://github.com/solidusio/solidus/blob/master/CONTRIBUTING.md#pull-request-guidelines)
- [ ] I have added a detailed description into each commit message
- [ ] I have updated Guides and README accordingly to this change (if needed)
- [ ] I have added tests to cover this change (if needed)
- [ ] I have added a CHANGELOG entry for this change (if needed)

Move issue reference in comment into PR template
Move issue reference in comment into PR template

It needs a better explanation so it's better to keep it into the
comment.
