Remove jest setting

Resolved at 23.5.0
jestjs/jest#6792

Author: abetomo

package.json

@@ -51,8 +51,5 @@
   ],
   "engines": {
     "node": ">= 6.0.0"
-  },
-  "jest": {
-    "testURL": "http://localhost/"
   }
 }