Chore: Update grafana-ui version to 6.2.0-alpha.0 (#17109)

packages/grafana-ui/package.json

 {
   "name": "@grafana/ui",
-  "version": "6.0.1-alpha.0",
+  "version": "6.2.0-alpha.0",
   "description": "Grafana Components Library",
   "keywords": [
     "typescript",