build(deps-dev): bump webpack-cli from 3.3.7 to 3.3.8

Bumps [webpack-cli](https://github.com/webpack/webpack-cli) from 3.3.7 to 3.3.8.
- [Release notes](https://github.com/webpack/webpack-cli/releases)
- [Changelog](https://github.com/webpack/webpack-cli/blob/v3.3.8/CHANGELOG.md)
- [Commits](webpack/webpack-cli@v3.3.7...v3.3.8)

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

Author: dependabot-preview[bot]

yarn.lock

@@ -6186,9 +6186,9 @@ webidl-conversions@^4.0.2:
   integrity sha512-YQ+BmxuTgd6UXZW3+ICGfyqRyHXVlD5GtQr5+qjiNW7bF0cqrzX500HVXPBOvgXb5YnzDd+h0zqyv61KUD7+Sg==
 
 webpack-cli@^3.3.6:
-  version "3.3.7"
-  resolved "https://registry.yarnpkg.com/webpack-cli/-/webpack-cli-3.3.7.tgz#77c8580dd8e92f69d635e0238eaf9d9c15759a91"
-  integrity sha512-OhTUCttAsr+IZSMVwGROGRHvT+QAs8H6/mHIl4SvhAwYywjiylYjpwybGx7WQ9Hkb45FhjtsymkwiRRbGJ1SZQ==
+  version "3.3.8"
+  resolved "https://registry.yarnpkg.com/webpack-cli/-/webpack-cli-3.3.8.tgz#caeaebcc26f685db1736e5decd3f01aac30123ec"
+  integrity sha512-RANYSXwikSWINjHMd/mtesblNSpjpDLoYTBtP99n1RhXqVI/wxN40Auqy42I7y4xrbmRBoA5Zy5E0JSBD5XRhw==
   dependencies:
     chalk "2.4.2"
     cross-spawn "6.0.5"