Bumps [rollup-plugin-commonjs](https://github.com/rollup/rollup-plugin-commonjs) from 9.3.1 to 9.3.4.
<details>
<summary>Changelog</summary>

*Sourced from [rollup-plugin-commonjs's changelog](https://github.com/rollup/rollup-plugin-commonjs/blob/master/CHANGELOG.md).*

> ## 9.3.4
> *2019-04-04*
> * Make "extensions" optional ([#384](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/384))
> * Use same typing for include and exclude properties ([#385](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/385))
> 
> ## 9.3.3
> *2019-04-04*
> * Remove colon from module prefixes ([#371](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/371))
> 
> ## 9.3.2
> *2019-04-04*
> * Use shared extractAssignedNames, fix destructuring issue ([#303](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/303))
</details>
<details>
<summary>Commits</summary>

- [`851ed8e`](rollup/rollup-plugin-commonjs@851ed8e) 9.3.4
- [`2c447af`](rollup/rollup-plugin-commonjs@2c447af) Update changelog
- [`5cb3b2d`](rollup/rollup-plugin-commonjs@5cb3b2d) set same typing to include and exclude properties ([#385](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/385))
- [`456a223`](rollup/rollup-plugin-commonjs@456a223) make "extensions" optional ([#384](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/384))
- [`3921f28`](rollup/rollup-plugin-commonjs@3921f28) 9.3.3
- [`28421a0`](rollup/rollup-plugin-commonjs@28421a0) Update changelog
- [`e63e57f`](rollup/rollup-plugin-commonjs@e63e57f) fix: remove colon from module prefixes ([#371](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/371))
- [`a34ebbc`](rollup/rollup-plugin-commonjs@a34ebbc) 9.3.2
- [`50696f3`](rollup/rollup-plugin-commonjs@50696f3) Update changelog
- [`34270d4`](rollup/rollup-plugin-commonjs@34270d4) Use extractAssignedNames from rollup-pluginutils. Resolves [#303](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/303) ([#383](https://github-redirect.dependabot.com/rollup/rollup-plugin-commonjs/issues/383))
- See full diff in [compare view](rollup/rollup-plugin-commonjs@v9.3.1...v9.3.4)
</details>
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