Update dependency classnames to v2.3.1

Author: renovate-bot

package.json

@@ -28,7 +28,7 @@
   },
   "dependencies": {
     "@plotly/draft-js-export-html": "1.2.0",
-    "classnames": "2.3.0",
+    "classnames": "2.3.1",
     "draft-js": "0.11.7",
     "draft-js-import-html": "1.4.1",
     "draft-js-utils": "1.4.0",