🤖 chore: Add test key in .babel.env.

These changes were automatically generated by a transform whose code can be found at:
  - https://github.com/aureooms/rejuvenate/blob/e2bf2c17f7e41fd818d2de9cb478d2e183f92a0e/src/transforms/package.json:ensure-babel-env-test.js
Please contact the author of the transform if you believe there was an error.

package.json

@@ -157,7 +157,8 @@
             }
           ]
         ]
-      }
+      },
+      "test": {}
     }
   },
   "xo": {