Update dependency prettier to v2.1.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
prettier (source)	devDependencies	minor	2.0.5 -> 2.1.0

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Release Notes

prettier/prettier

### [`v2.1.0`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#​210) [Compare Source](https://togithub.com/prettier/prettier/compare/2.0.5...2.1.0) [diff](https://togithub.com/prettier/prettier/compare/2.0.5...2.1.0) 🔗 [Release Notes](https://prettier.io/blog/2020/08/24/2.1.0.html)

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