Update dependency style-loader to v0.21.0

[renovate[bot]]

This Pull Request updates dependency style-loader from v0.20.3 to v0.21.0

Note: This PR was created on a configured schedule ("before 5am on monday") and will not receive updates outside those times.

Release Notes

### [`v0.21.0`](https://github.com/webpack-contrib/style-loader/blob/master/CHANGELOG.md#​0210httpsgithubcomwebpack-contribstyle-loadercomparev0203v0210-2018-04-18) ##### Features * enable tag type configuration ([#​316](`https://github.com/webpack-contrib/style-loader/issues/316`)) ([892cba5](https://github.com/webpack-contrib/style-loader/commit/892cba5)) #### [0.20.3](https://github.com/webpack-contrib/style-loader/compare/v0.20.2...v0.20.3) (2018-03-09) ##### Bug Fixes * **package:** update `schema-utils` v0.4.3...0.4.5 (`dependencies`) ([#​308](`https://github.com/webpack-contrib/style-loader/issues/308`)) ([9455888](https://github.com/webpack-contrib/style-loader/commit/9455888)) #### [0.20.2](https://github.com/webpack-contrib/style-loader/compare/v0.20.1...v0.20.2) (2018-02-15) ##### Bug Fixes * **urls:** skip empty `url()` handling ([#​304](`https://github.com/webpack-contrib/style-loader/issues/304`)) ([64f12dc](https://github.com/webpack-contrib/style-loader/commit/64f12dc)) #### [0.20.1](https://github.com/webpack-contrib/style-loader/compare/v0.20.0...v0.20.1) (2018-01-26) ##### Bug Fixes * **index:** source code indentation ([#​299](`https://github.com/webpack-contrib/style-loader/issues/299`)) ([b4642e7](https://github.com/webpack-contrib/style-loader/commit/b4642e7)) ---

Commits

#### v0.21.0 - [`78ca637`](https://github.com/webpack-contrib/style-loader/commit/78ca637690c29db2052e7dfb81b3fae69a8b12ba) ci(circle): Swap out travis for CircleCI 2.0 config - [`91902a0`](https://github.com/webpack-contrib/style-loader/commit/91902a08833ff27be4ac44de0e6b3a33a04273af) chore(package): Adds nsp for security check - [`2c1d451`](https://github.com/webpack-contrib/style-loader/commit/2c1d45137fcd6366c8fa687fa71867dd5ae2b8af) ci(circle): Short circuit canary suite - [`342b3c6`](https://github.com/webpack-contrib/style-loader/commit/342b3c6e3cf3d5d32cda8b51814a054640b53b15) ci(circle): Use single thread jest script - [`2c3e6b5`](https://github.com/webpack-contrib/style-loader/commit/2c3e6b57ac8abbd895047ae8b70620d27e95fbd4) ci(circle): Removes setup docker command - [`892cba5`](https://github.com/webpack-contrib/style-loader/commit/892cba5ad5d654e1db027b96f82caf683cbd29bb) feat: enable tag type configuration (#​316) - [`e4fa68a`](https://github.com/webpack-contrib/style-loader/commit/e4fa68a19d2390e265e27ec60ae928bf80a41228) chore(release): 0.21.0

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