Bump pressbooks-build-tools from 1.2.0 to 1.2.1 (#165)

Bumps [pressbooks-build-tools](https://github.com/pressbooks/pressbooks-build-tools) from 1.2.0 to 1.2.1.
<details>
<summary>Release notes</summary>

*Sourced from [pressbooks-build-tools's releases](https://github.com/pressbooks/pressbooks-build-tools/releases).*

> ## 1.2.1
> ### Patches 
> 
> - Bump rimraf from 2.6.2 to 2.6.3: [#220](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/220)
> - Bump laravel-mix from 4.0.12 to 4.0.13: [#222](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/222)
> - Bump eslint-plugin-react from 7.12.1 to 7.12.2: [#221](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/221)
> - Bump eslint-plugin-flowtype from 3.2.0 to 3.2.1: [#226](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/226)
> - Bump eslint-plugin-react from 7.12.2 to 7.12.3: [#225](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/225)
> - Bump sass from 1.15.2 to 1.15.3: [#224](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/224)
> - Bump vue-template-compiler from 2.5.21 to 2.5.22: [#229](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/229)
</details>
<details>
<summary>Commits</summary>

- [`d7dc8a9`](d7dc8a9225) 1.2.1
- [`ec0e50c`](ec0e50c3a9) Bump vue-template-compiler from 2.5.21 to 2.5.22 ([#229](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/229))
- [`2b877c9`](2b877c934f) Bump sass from 1.15.2 to 1.15.3 ([#224](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/224))
- [`820cc27`](820cc27794) Bump eslint-plugin-react from 7.12.2 to 7.12.3 ([#225](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/225))
- [`7863e6a`](7863e6a6f5) Bump eslint-plugin-flowtype from 3.2.0 to 3.2.1 ([#226](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/226))
- [`a23c743`](a23c7438d7) Bump eslint-plugin-react from 7.12.1 to 7.12.2 ([#221](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/221))
- [`e97e77b`](e97e77b673) Bump laravel-mix from 4.0.12 to 4.0.13 ([#222](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/222))
- [`30b1e2f`](30b1e2f5f1) Bump rimraf from 2.6.2 to 2.6.3 ([#220](https://github-redirect.dependabot.com/pressbooks/pressbooks-build-tools/issues/220))
- See full diff in [compare view](https://github.com/pressbooks/pressbooks-build-tools/compare/1.2.0...1.2.1)
</details>
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package.json

@@ -60,7 +60,7 @@
 		"node": ">= 6.9.4"
 	},
 	"devDependencies": {
-		"pressbooks-build-tools": "^1.2.0",
+		"pressbooks-build-tools": "^1.2.1",
 		"sass": "^1.15.2",
 		"sass-loader": "^7.1.0",
 		"vue-template-compiler": "^2.5.21"