chore(deps): update dependency prettier to v2.8.4

Author: renovate[bot]

package.json

@@ -57,7 +57,7 @@
     "jest-circus": "26.6.3",
     "js-yaml": "3.14.1",
     "mockttp": "1.2.0",
-    "prettier": "2.2.1",
+    "prettier": "2.8.4",
     "rimraf": "3.0.2",
     "ts-jest": "26.5.1",
     "ts-node": "9.1.1",