Fix fetching unavailable (deleted, private) videos throwing unrelated exceptions instead of VideoUnavailableException

[Tyrrrz]

No description provided.

[Copilot]

Pull Request Overview

This pull request fixes tests for language-specific streams by updating expected language names and improving error handling in the stream client. The changes address test failures likely caused by changes in YouTube's language name formatting.

• Updated expected language names in tests to match current YouTube API responses
• Enhanced exception handling to only retry on specific video unplayability scenarios
• Improved code organization by moving a comment to a more logical position

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
YoutubeExplode/Videos/Streams/StreamClient.cs	Enhanced exception handling to filter retry logic and reorganized comments
YoutubeExplode.Tests/StreamSpecs.cs	Updated expected language names from full country names to abbreviated formats

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (dad9248) to head (7679871).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

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