Upgrade to MediaElement 2.16.2
https://github.com/johndyer/mediaelement/compare/2.15.1...2.16.2

Fixes #30281.

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Remove an invalid parameter from the DocBlock for the `gallery_style` hook.

Props keesiemeijer.
Fixes #30507.

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Ensure uniqueness when returning page lists in `get_page_children()`. Fixes failing unit tests.

Props boonebgorges.
Reverts [30246].
Fixes #14477.

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IETF language changes in MediaElement:
https://github.com/johndyer/mediaelement/pull/1270/

Reverts [28801].
Fixes #29182.

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