build(deps): Bump yargs from 13.2.1 to 13.2.2 (#25)

Bumps [yargs](https://github.com/yargs/yargs) from 13.2.1 to 13.2.2.
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<summary>Changelog</summary>

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

> ## [13.2.2](yargs/yargs@v13.2.1...v13.2.2) (2019-03-06)
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<summary>Commits</summary>

- [`e7f2937`](yargs/yargs@e7f2937) chore(release): 13.2.2
- [`edd0bb5`](yargs/yargs@edd0bb5) test: correct test description
- [`03a9523`](yargs/yargs@03a9523) chore: forgoing dropping Node 6 until yargs@14 ([#1308](https://github-redirect.dependabot.com/yargs/yargs/issues/1308))
- [`14920d1`](yargs/yargs@14920d1) docs: remove --save option as it isn't required anymore ([#1301](https://github-redirect.dependabot.com/yargs/yargs/issues/1301))
- [`545c7f1`](yargs/yargs@545c7f1) test: slightly reworded one test
- See full diff in [compare view](yargs/yargs@v13.2.1...v13.2.2)
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