Update dependency prettier to v2.8.7

Author: renovate[bot]

package.json

@@ -21,7 +21,7 @@
     "@types/node": "13.13.52",
     "husky": "6.0.0",
     "lint-staged": "10.5.4",
-    "prettier": "2.3.2",
+    "prettier": "2.8.7",
     "tslint": "6.1.3",
     "tslint-config-prettier": "1.18.0",
     "tslint-plugin-prettier": "2.3.0"