Icons: Add brain icon (#116023)

* Icons: Add brain icon

* lint

* Add brain to cached icons

packages/grafana-data/src/types/icon.ts

@@ -52,6 +52,7 @@ export const availableIconsIndex = {
   bookmark: true,
   'book-open': true,
   'brackets-curly': true,
+  brain: true,
   'browser-alt': true,
   bug: true,
   building: true,

public/app/core/icons/cached.json

@@ -29,6 +29,7 @@
   "unicons/bookmark",
   "unicons/book-open",
   "unicons/brackets-curly",
+  "unicons/brain",
   "unicons/bug",
   "unicons/building",
   "unicons/calculator-alt",