Update dependency extract-loader to v5.1.0

Author: renovate-bot

package-lock.json

@@ -46,7 +46,7 @@
     "eslint": "6.8.0",
     "eslint-config-unobtrusive": "1.2.5",
     "eslint-plugin-babel": "5.3.0",
-    "extract-loader": "5.0.1",
+    "extract-loader": "5.1.0",
     "file-loader": "6.0.0",
     "flexsearch": "0.6.32",
     "fs-extra": "9.0.0",