Update dependency prettier to v2.8.8

Author: renovate[bot]

package.json

@@ -45,7 +45,7 @@
 		"hardhat": "2.9.9",
 		"hardhat-abi-exporter": "2.3.0",
 		"hardhat-gas-reporter": "1.0.9",
-		"prettier": "2.8.4",
+		"prettier": "2.8.8",
 		"prettier-plugin-solidity": "1.1.2",
 		"solhint": "3.3.8",
 		"solidity-coverage": "0.8.2",

yarn.lock

@@ -8754,10 +8754,10 @@ [email protected]:
     semver "^7.3.8"
     solidity-comments-extractor "^0.0.7"
 
-[email protected].4:
-  version "2.8.4"
-  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.8.4.tgz#34dd2595629bfbb79d344ac4a91ff948694463c3"
-  integrity sha512-vIS4Rlc2FNh0BySk3Wkd6xmwxB0FpOndW5fisM5H8hsZSxU2VWVB5CWIkIjWvrHjIhxk2g3bfMKM87zNTrZddw==
+[email protected].8:
+  version "2.8.8"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.8.8.tgz#e8c5d7e98a4305ffe3de2e1fc4aca1a71c28b1da"
+  integrity sha512-tdN8qQGvNjw4CHbY+XXk0JgCXn9QiF21a55rBe5LJAU+kDyC4WQn4+awm2Xfk2lQMk5fKup9XgzTZtGkjBdP9Q==
 
 prettier@^1.14.3:
   version "1.19.1"