chore(deps): update dependency is-docker to v2.2.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
is-docker	2.1.1 -> 2.2.1

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Release Notes

sindresorhus/is-docker

### [`v2.2.1`](https://togithub.com/sindresorhus/is-docker/releases/v2.2.1) [Compare Source](https://togithub.com/sindresorhus/is-docker/compare/v2.2.0...v2.2.1) - Revert "Improve detection" [`5d370e4`](https://togithub.com/sindresorhus/is-docker/commit/5d370e4) It unfortunately caused more problems than it solved. See: [#​10 (comment)](https://togithub.com/sindresorhus/is-docker/issues/10#issuecomment-816138643) ### [`v2.2.0`](https://togithub.com/sindresorhus/is-docker/releases/v2.2.0) [Compare Source](https://togithub.com/sindresorhus/is-docker/compare/v2.1.1...v2.2.0) - Improve detection [`02633ab`](https://togithub.com/sindresorhus/is-docker/commit/02633ab)

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