Enable usage of Corepack (#2366)

Corepack chooses package manager to use with the
field `packageManager`. For users using Yarn
through Corepack, this is a real convenience.

Co-authored-by: Daishi Kato <[email protected]>

Author: onlined

package.json

@@ -266,5 +266,6 @@
     "react": {
       "optional": true
     }
-  }
+  },
+  "packageManager": "[email protected]+sha256.dbed5b7e10c552ba0e1a545c948d5473bc6c5a28ce22a8fd27e493e3e5eb6370"
 }