Bump xo from 0.55.1 to 0.56.0

Bumps [xo](https://github.com/xojs/xo) from 0.55.1 to 0.56.0.
- [Release notes](https://github.com/xojs/xo/releases)
- [Commits](xojs/xo@v0.55.1...v0.56.0)

---
updated-dependencies:
- dependency-name: xo
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -51,7 +51,7 @@
     "ava": "^5.3.1",
     "execa": "^7.2.0",
     "markdownlint-cli-local-test-rule": "./test/custom-rules/markdownlint-cli-local-test-rule",
-    "xo": "^0.55.1"
+    "xo": "^0.56.0"
   },
   "xo": {
     "prettier": true,