chore(deps): update dependency cssnano to v5.1.15

Author: renovate[bot]

package-lock.json

@@ -40,7 +40,7 @@
     "babel-loader": "^9.1.2",
     "core-js": "^3.27.1",
     "css-minimizer-webpack-plugin": "4.2.2",
-    "cssnano": "5.1.14",
+    "cssnano": "5.1.15",
     "eslint": "^8.32.0",
     "eslint-config-prettier": "^8.6.0",
     "eslint-plugin-babel": "5.3.1",