chore(deps): bump pusher-js from 5.0.3 to 5.1.1

Bumps [pusher-js](https://github.com/pusher/pusher-js) from 5.0.3 to 5.1.1.
- [Release notes](https://github.com/pusher/pusher-js/releases)
- [Changelog](https://github.com/pusher/pusher-js/blob/master/CHANGELOG.md)
- [Commits](pusher/pusher-js@v5.0.3...v5.1.1)

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