Bump koa-websocket from 5.0.1 to 6.0.0

Bumps [koa-websocket](https://github.com/kudos/koa-websocket) from 5.0.1 to 6.0.0.
- [Release notes](https://github.com/kudos/koa-websocket/releases)
- [Changelog](https://github.com/kudos/koa-websocket/blob/master/CHANGELOG.md)
- [Commits](https://github.com/kudos/koa-websocket/compare/5.0.1...6.0.0)

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

package.json

@@ -68,7 +68,7 @@
     "koa-session": "^5.10.1",
     "koa-static": "^5.0.0",
     "koa-views": "^6.2.1",
-    "koa-websocket": "^5.0.1",
+    "koa-websocket": "^6.0.0",
     "kue": "^0.11.6",
     "mime-types": "^2.1.26",
     "moment": "^2.24.0",