Update del requirement from ^4.1.1 to ^5.0.0

Updates the requirements on [del](https://github.com/sindresorhus/del) to permit the latest version.
- [Release notes](https://github.com/sindresorhus/del/releases)
- [Commits](https://github.com/sindresorhus/del/compare/v4.1.1...v5.0.0)

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

package.json

@@ -43,7 +43,7 @@
     "cpy": "^7.2.0",
     "cross-env": "^5.2.0",
     "cssnano": "^4.1.10",
-    "del": "^4.1.1",
+    "del": "^5.0.0",
     "eslint": "^5.16.0",
     "eslint-config-airbnb-base": "^13.1.0",
     "eslint-plugin-import": "^2.17.3",