chore: remove obsolete scripts from root package.json

Author: tkajtoch

package.json

@@ -10,9 +10,6 @@
   },
   "scripts": {
     "pre-push": "yarn --cwd packages/eui pre-push",
-    "preinstall": "printf $'\\x1b[K\\x1b[37;41mWarning: EUI has recently migrated to a monorepo structure. Please run EUI scripts like \\x1b[1;4myarn start\\x1b[0m\\x1b[37;41m or \\x1b[1;4myarn build\\x1b[0m\\x1b[37;41m from the \\x1b[1;4mpackages/eui\\x1b[0m\\x1b[37;41m directory instead!\\n\\nIf this is the first time you\\'re running EUI after the monorepo migration, please run this first from the root repository\\'s directory to clean up your local environment:\\n  \\x1b[1;4mrm -rf node_modules .cache-loader dist es lib optimize test-env types .eslintcache .loki reports docs .nyc_output eui.d.ts && yarn\\x1b[0m\\x1b[37;41m\\n\\nInstall process will continue in 10 seconds...\\x1b[0m'; sleep 10",
-    "start": "printf $'\\x1b[K\\x1b[37;41mPlease run this script from the \\x1b[1;4mpackages/eui\\x1b[0m\\x1b[37;41m directory instead\\x1b[0m\\n'; exit 1",
-    "build": "printf $'\\x1b[K\\x1b[37;41mPlease run this script from the \\x1b[1;4mpackages/eui\\x1b[0m\\x1b[37;41m directory instead\\x1b[0m\\n'; exit 1",
     "release": "node scripts/release",
     "clean": "node scripts/clean.mjs"
   },