Update dependency prettier to v2.7.1

Author: renovate[bot]

package-lock.json

@@ -53,7 +53,7 @@
     "mocha": "9.2.2",
     "nock": "13.2.9",
     "nyc": "15.1.0",
-    "prettier": "2.6.2",
+    "prettier": "2.7.1",
     "ts-node": "10.9.1",
     "typescript": "3.9.10",
     "vuepress": "1.9.7"