Plyr play error

Summary

Part-way to closing #2377 (closed)

When debugging I noticed errors being thrown from Plyr before the parent components init had succeeded; This raised an alarm bell as media pages should not be auto-playing to start with. The modals should be when they are clicked, but not on a media page.

It appears as though if autoplay is provided as an @input, it tries to auto-play straight away, in turn throwing an error because the component is not ready https://developers.google.com/web/updates/2017/06/play-request-was-interrupted

Steps to test

On production, just open your console and load a video (e.g. the randomly selected https://fix-autoplay-bug-2377.minds.io/media/1044356662615347220)

To test, check this error does not show on the sandbox.

Estimated Regression Scope

I can only foresee the worst-case scenario as being a regression in the auto-playing of videos; perhaps when opening a modal; this is not the case though by my testing.