Webtorrent: Add browser testing for Safari

[feross]

We currently only test WebTorrent on Chrome and Firefox. Let's add Safari to the list.

[axelonet]

I just ran the HTML file from docs and added a magnet link. It started streaming the file. In safari of course. What else do I need to do to make webtorrent safari compatible,

[norzak]

Looks like removing a torrent from seeding corrupts Webtorrent on Safari.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[feross]

I added Safari to the airtap testing list a while ago. So this task is complete now.