applied @dirkf's patches for nsig extraction on youtube

[aiur-adept]

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Description of your pull request and other information

Fixes nsig extraction for youtube

See #32885

[dirkf]

Here's the extra change. I thought there was also a diff against the original patch but apparently not.

[dirkf]

Fixed formatting.

[dirkf]

Thanks for helping out!

The tests all work. You might like to pull the updated version and try running python test/test_youtube_signature.py TestSignature.test_nsig_js_20dfca59 as-is and then after patching if not func_name: to if True or not func_name:, to test the fallback from yt-dlp (again). If that's OK we can merge.

[aiur-adept]

LGTM