fix: packages/sandbox-hooks/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-CROSSSPAWN-8303230
- https://snyk.io/vuln/SNYK-JS-MINIMATCH-3050818

Author: snyk-bot

packages/sandbox-hooks/package.json

@@ -15,7 +15,7 @@
     "codesandbox-api": "0.0.32",
     "console-feed": "^3.1.9",
     "css-line-break": "^1.1.1",
-    "react-dev-utils": "^3.1.2"
+    "react-dev-utils": "^12.0.0"
   },
   "devDependencies": {
     "@babel/core": "^7.6.4",