Bump @babylonjs/gui from 5.17.1 to 5.31.2 in /docs/visualiser

Bumps [@babylonjs/gui](https://github.com/BabylonJS/Babylon.js) from 5.17.1 to 5.31.2.
- [Release notes](https://github.com/BabylonJS/Babylon.js/releases)
- [Changelog](https://github.com/BabylonJS/Babylon.js/blob/master/CHANGELOG.md)
- [Commits](BabylonJS/Babylon.js@5.17.1...5.31.2)

---
updated-dependencies:
- dependency-name: "@babylonjs/gui"
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

docs/visualiser/package.json

@@ -1,7 +1,7 @@
 {
   "dependencies": {
     "@babylonjs/core": "^5.17.1",
-    "@babylonjs/gui": "^5.17.1"
+    "@babylonjs/gui": "^5.31.2"
   },
   "devDependencies": {
     "ts-loader": "^9.4.1",