Bump cross-env from 5.1.1 to 5.1.5

Bumps [cross-env](https://github.com/kentcdodds/cross-env) from 5.1.1 to 5.1.5.
- [Release notes](https://github.com/kentcdodds/cross-env/releases)
- [Changelog](https://github.com/kentcdodds/cross-env/blob/master/CHANGELOG.md)
- [Commits](kentcdodds/cross-env@v5.1.1...v5.1.5)

Signed-off-by: dependabot[bot] <support@dependabot.com>

yarn.lock

@@ -1262,8 +1262,8 @@ coveralls@^2.13.1:
     request "2.79.0"
 
 cross-env@^5.1.1:
-  version "5.1.1"
-  resolved "https://registry.yarnpkg.com/cross-env/-/cross-env-5.1.1.tgz#b6d8ab97f304c0f71dae7277b75fe424c08dfa74"
+  version "5.1.5"
+  resolved "https://registry.yarnpkg.com/cross-env/-/cross-env-5.1.5.tgz#31daf7f3a52ef337c8ddda585f08175cce5d1fa5"
   dependencies:
     cross-spawn "^5.1.0"
     is-windows "^1.0.0"