chore(deps): update dependency prettier to v2.8.7

Author: renovate[bot]

package.json

@@ -27,7 +27,7 @@
     "@types/turndown": "5.0.0",
     "ava": "3.15.0",
     "del-cli": "3.0.1",
-    "prettier": "2.2.1",
+    "prettier": "2.8.7",
     "semantic-release": "17.3.7",
     "ts-node": "9.1.1",
     "typescript": "4.1.3"