⬆️ deps: Upgrade dependency xo to v0.56.0

Author: renovate[bot]

package.json

@@ -88,7 +88,7 @@
     "power-assert": "1.6.1",
     "regenerator-runtime": "0.14.0",
     "string-algorithms": "1.0.31",
-    "xo": "0.53.1"
+    "xo": "0.56.0"
   },
   "ava": {
     "files": [