Update dependency optimize-css-assets-webpack-plugin to v5.0.8

Author: renovate-bot

package.json

@@ -132,7 +132,7 @@
     "webpack": "4.46.0",
     "webpack-cli": "4.7.2",
     "webpack-dev-server": "3.11.2",
-    "optimize-css-assets-webpack-plugin": "5.0.7",
+    "optimize-css-assets-webpack-plugin": "5.0.8",
     "terser-webpack-plugin": "4.2.3",
     "webpack-merge": "4.2.2"
   }