build(deps): bump video.js from 7.21.5 to 8.21.0

Bumps [video.js](https://github.com/videojs/video.js) from 7.21.5 to 8.21.0.
- [Release notes](https://github.com/videojs/video.js/releases)
- [Changelog](https://github.com/videojs/video.js/blob/main/CHANGELOG.md)
- [Commits](videojs/video.js@v7.21.5...v8.21.0)

---
updated-dependencies:
- dependency-name: video.js
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

package.json

@@ -47,7 +47,7 @@
     "md5": "^2.3.0",
     "moment": "^2.30.1",
     "posthog-js": "^1.194.6",
-    "video.js": "7.21.5",
+    "video.js": "7.21.6",
     "vue": "^3.5.13",
     "vue-loader": "^17.4.2",
     "vue-markdown": "^2.2.4",