Updated install-once script

- Changed install-once script to use && instead of concurrently

Author: MaxWeisen

package.json

@@ -57,7 +57,7 @@
     "xterm-for-react": "^1.0.4"
   },
   "scripts": {
-    "install-once": "concurrently \"npm i\" \"npm run electron-rebuild\"",
+    "install-once": "npm i && npm run electron-rebuild",
     "test": "react-app-rewired test --env=jsdom",
     "test:e2e": "./node_modules/mocha/bin/mocha src/__tests__/spec.e2e.js",
     "test:integra": "mocha src/__tests__/spec.integra.js",