Update dependency prettier to v2

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
prettier (source)	devDependencies	major	1.19.1 -> 2.0.2

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Release Notes

prettier/prettier

### [`v2.0.2`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#​202) [Compare Source](https://togithub.com/prettier/prettier/compare/2.0.1...2.0.2) [diff](https://togithub.com/prettier/prettier/compare/2.0.1...2.0.2) ##### 2.0 regressions ##### JavaScript: Fix formatting of pseudo-elements and pseudo-classes in styled-components template literals ([#​7842](https://togithub.com/prettier/prettier/pull/7842) by [@​thorn0](https://togithub.com/thorn0)) ```jsx // Input const Foo = styled.div` ${media.smallDown}::before {} `; // Prettier 2.0.0 const Foo = styled.div` ${media.smallDown}: : before{ } `; // Prettier 2.0.2 const Foo = styled.div` ${media.smallDown}::before { } `; ``` ##### TypeScript: Avoid trailing commas on index signatures with only one parameter ([#​7836](https://togithub.com/prettier/prettier/pull/7836) by [@​bakkot](https://togithub.com/bakkot)) TypeScript index signatures technically allow multiple parameters and trailing commas, but it's an error to have multiple parameters there, and Babel's TypeScript parser does not accept them. So Prettier now avoids putting a trailing comma there when you have only one parameter. ```ts // Input export type A = { a?: { [ x: string ]: typeof SomeLongLongLongTypeName[keyof typeof SomeLongLongLongTypeName]; } | null; }; // Prettier 2.0.0 export type A = { a?: { [ x: string, ]: typeof SomeLongLongLongTypeName[keyof typeof SomeLongLongLongTypeName]; } | null; }; // Prettier 2.0.2 export type A = { a?: { [ x: string ]: typeof SomeLongLongLongTypeName[keyof typeof SomeLongLongLongTypeName]; } | null; }; ``` ##### Revert "markdown: fix redundant leading spaces in markdown list" ([#​7847](https://togithub.com/prettier/prettier/pull/7847)) See [#​7846](https://togithub.com/prettier/prettier/issues/7846) ##### Other changes ##### TypeScript: Fix `prettier-ignore` in union types ([#​7798](https://togithub.com/prettier/prettier/pull/7798) by [@​thorn0](https://togithub.com/thorn0)) ```ts // Input export type a = // foo | foo1&foo2 // prettier-ignore | bar1&bar2 // baz | baz1&baz2; // Prettier 2.0.0 export type a = // foo | foo1&foo2 // prettier-ignore // prettier-ignore | (bar1 & bar2) // baz | (baz1 & baz2); // Prettier 2.0.2 export type a = // foo | (foo1 & foo2) // prettier-ignore | bar1&bar2 // baz | (baz1 & baz2); ``` ### [`v2.0.1`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#​201) [Compare Source](https://togithub.com/prettier/prettier/compare/2.0.0...2.0.1) [diff](https://togithub.com/prettier/prettier/compare/2.0.0...2.0.1) ##### API: Fix build script to not corrupt `import-fresh` module ([#​7820](https://togithub.com/prettier/prettier/pull/7820) by [@​thorn0](https://togithub.com/thorn0)) ### [`v2.0.0`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#​200) [Compare Source](https://togithub.com/prettier/prettier/compare/1.19.1...2.0.0) [diff](https://togithub.com/prettier/prettier/compare/1.19.1...2.0.0) 🔗 [Release Notes](https://prettier.io/blog/2020/03/21/2.0.0.html)

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