[Vimeo] Add extractor for event media

[dirkf]

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• Searched the bugtracker for similar pull requests
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What is the purpose of your pull request?

• Bug fix
• Improvement
• New extractor
• New feature

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Description of your pull request and other information

As reported in issue #29380 and documented here, Vimeo supports embedded media for events, with URLs not supported by the current Vimeo extractors.

This PR adds an extractor for such embedded media and also adds the embed pattern to the list that is used for the generic extractor.

Closes #29380.