SDK / exoplayer

Release is a life cycle operation that should only be called when
the player is no longer needed. It's linked to the player lifecycle
and thus very different from prepare/stop.
As a result, it should not be in the same command.

Additionally it's not clear if remote players will ever need to call release,
as the player creator is best candidate to release it.

As a result the release operation doesn't have a use case for a command.
A release command can be added later if a need is identified.

PiperOrigin-RevId: 370649214