Bump stylelint and stylelint-config-standard

Bumps [stylelint](https://github.com/stylelint/stylelint) and [stylelint-config-standard](https://github.com/stylelint/stylelint-config-standard). These dependencies needed to be updated together.

Updates `stylelint` from 8.4.0 to 13.2.1
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/master/CHANGELOG.md)
- [Commits](stylelint/stylelint@8.4.0...13.2.1)

Updates `stylelint-config-standard` from 17.0.0 to 20.0.0
- [Release notes](https://github.com/stylelint/stylelint-config-standard/releases)
- [Changelog](https://github.com/stylelint/stylelint-config-standard/blob/master/CHANGELOG.md)
- [Commits](stylelint/stylelint-config-standard@17.0.0...20.0.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

package.json

@@ -76,8 +76,8 @@
     "react-markdown": "4.3.1",
     "rlp": "2.2.4",
     "style-loader": "^0.23.1",
-    "stylelint": "^8.2.0",
-    "stylelint-config-standard": "^17.0.0",
+    "stylelint": "^13.2.1",
+    "stylelint-config-standard": "^20.0.0",
     "url-loader": "^1.1.2",
     "validator": "13.0.0",
     "web3": "1.2.2",