Update dependency eslint-plugin-react to v7.21.4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
eslint-plugin-react	devDependencies	patch	7.21.3 -> 7.21.4

---

Release Notes

yannickcr/eslint-plugin-react

### [`v7.21.4`](https://togithub.com/yannickcr/eslint-plugin-react/blob/master/CHANGELOG.md#​7214---20201009) [Compare Source](https://togithub.com/yannickcr/eslint-plugin-react/compare/v7.21.3...v7.21.4) ##### Fixed - [`no-unused-prop-types`]: Silence false positive on `never` type in TS ([#​2815][] [@​pcorpet](https://togithub.com/pcorpet)) - [`jsx-indent-props`]: Apply indentation when operator is used in front of the upper line ([#​2808][], [#​2820][] [@​Moong0122](https://togithub.com/Moong0122)) - [Deps] update `jsx-ast-utils` ([#​2822][] [jsx-eslint/jsx-ast-utils#​102][] [@​ljharb](https://togithub.com/ljharb)) [7.21.4]: https://togithub.com/yannickcr/eslint-plugin-react/compare/v7.21.3...v7.21.4 [#​2822]: https://togithub.com/yannickcr/eslint-plugin-react/issues/2822 [#​2820]: https://togithub.com/yannickcr/eslint-plugin-react/pull/2820 [#​2815]: https://togithub.com/yannickcr/eslint-plugin-react/pull/2815 [#​2808]: https://togithub.com/yannickcr/eslint-plugin-react/pull/2808 [jsx-eslint/jsx-ast-utils#​102]: https://togithub.com/jsx-eslint/jsx-ast-utils/pull/102

---

Renovate configuration

:date: Schedule: At any time (no schedule defined).

:vertical_traffic_light: Automerge: Disabled by config. Please merge this manually once you are satisfied.

:recycle: Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

:no_bell: Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR has been generated by WhiteSource Renovate. View repository job log here.