Remove irrelevant moz* features of HTMLMediaElement (#13794)
Remove irrelevant moz* features of HTMLMediaElement (#13794)

These have all been removed long enough ago to be considered irrelevant:
https://github.com/mdn/browser-compat-data/blob/main/docs/data-guidelines.md#removal-of-irrelevant-features
mdn/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data