To address a Prototype Pollution vulnerability,
which exists in `mixin-deep` package, versions
`>=2.0.0 <2.0.1 || <1.3.2` (CVE-2019-10746).

- Diff: https://github.com/jonschlinkert/mixin-deep/compare/1.3.1...1.3.2
- Synk ID: https://app.snyk.io/vuln/SNYK-JS-MIXINDEEP-450212Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>