Update dependency prettier to v2.8.7

Author: renovate[bot]

package.json

@@ -60,7 +60,7 @@
     "jest": "27.4.0",
     "nodemon": "1.19.4",
     "ora": "6.0.1",
-    "prettier": "2.4.1",
+    "prettier": "2.8.7",
     "ts-jest": "27.0.7",
     "tslint": "latest",
     "tslint-config-prettier": "1.17.0",