[ie/crunchyroll] Fix stream extraction

[bashonly]

Credit to @stratuma for finding this solution. Also thanks to @napgiver for bringing this to my attention

The extractor needs to use the Switch user-agent when making the stream endpoint request, and subsequently needs to invalidate the stream token to prevent being rate-limited.

This PR also fixes an oversight in cb2fb4a that caused the extractor to not always make metadata available, as noted here

Fixes #9994

Template

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• Fix or improvement to an extractor (Make sure to add/update tests)