chore(schematics): use rc.0 for cli

Author: Lipata

projects/igniteui-angular/package.json

@@ -84,7 +84,7 @@
         "web-animations-js": "^2.3.2"
     },
     "igxDevDependencies": {
-        "@igniteui/angular-schematics": "~12.0.800-alpha.1"
+        "@igniteui/angular-schematics": "~12.0.800-rc.0"
     },
     "ng-update": {
         "migrations": "./migrations/migration-collection.json"