🤖 chore(package.json): Add devDependency xo.

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  - https://github.com/aureooms/rejuvenate/blob/e086830dfe927964be93f46b8ecdacd2597eb487/src/transforms/deps:add-xo.js
Please contact the author of the transform if you believe there was an error.

Author: a-flying-potato

package.json

@@ -70,7 +70,8 @@
     "int": "0.2.0",
     "np": "7.4.0",
     "power-assert": "1.6.1",
-    "regenerator-runtime": "0.13.7"
+    "regenerator-runtime": "0.13.7",
+    "xo": "0.38.2"
   },
   "ava": {
     "files": [