chore(deps-dev): bump cssnano from 5.0.17 to 5.1.7 (#753)

Bumps [cssnano](https://github.com/cssnano/cssnano) from 5.0.17 to 5.1.7.
- [Release notes](https://github.com/cssnano/cssnano/releases)
- [Commits](https://github.com/cssnano/cssnano/compare/cssnano@5.0.17...cssnano@5.1.7)

---
updated-dependencies:
- dependency-name: cssnano
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

package.json

@@ -59,7 +59,7 @@
     "@types/react-dom": "17.0.14",
     "autoprefixer": "10.4.2",
     "babel-loader": "8.2.3",
-    "cssnano": "5.0.17",
+    "cssnano": "5.1.7",
     "dts-cli": "1.2.0",
     "eslint-config-react-app": "7.0.0",
     "eslint-plugin-prettier": "4.0.0",