fix to 'Unable to extract nsig jsi ... #32842'

[tansy]

fix to 'Unable to extract nsig jsi ... #32842'
thanks to @Duster98 @#issuecomment-2220376175

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Fix to issue #32842 posted by @Duster98.

Code checked and tested.

$ python youtube-dl.py -F -v https://www.youtube.com/watch?v=NjCVZ2TBlkw
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'-F', u'-v', u'https://www.youtube.com/watch?v=NjCVZ2TBlkw']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2024.07.08 [a452f9437]
[debug] ** This version was built from the latest master code at https://github.com/ytdl-org/youtube-dl.
[debug] ** For support, visit the main site.
[debug] Python 2.7.3 (CPython i686 32bit) - Linux-i686 - OpenSSL 1.0.1e - glibc 2.0
[debug] exe versions: none
[debug] Proxy map: {}
[youtube] NjCVZ2TBlkw: Downloading webpage
[debug] [youtube] Decrypted nsig GGMy0_8ADhuvb3QiC => HhLGoGWp5YkFLQ
[debug] [youtube] Decrypted nsig g_flXTUre97dIvcKl => kBjCgNdd7NUQcQ
[info] Available formats for NjCVZ2TBlkw:
format code  extension  resolution note
251          webm       audio only audio_quality_medium    3k , webm_dash container, opus  (48000Hz), 2.57MiB
251-drc      webm       audio only audio_quality_medium    3k , webm_dash container, opus  (48000Hz), 2.58MiB
140          m4a        audio only audio_quality_medium  129k , m4a_dash container, mp4a.40.2 (44100Hz), 91.90MiB
140-drc      m4a        audio only audio_quality_medium  129k , m4a_dash container, mp4a.40.2 (44100Hz), 91.90MiB
160          mp4        256x144    144p    6k , mp4_dash container, avc1.4d400c, 30fps, video only, 4.70MiB
134          mp4        640x360    360p   10k , mp4_dash container, avc1.4d401e, 30fps, video only, 7.64MiB
136          mp4        1280x720   720p   21k , mp4_dash container, avc1.64001f, 30fps, video only, 15.16MiB
137          mp4        1920x1080  1080p   32k , mp4_dash container, avc1.640028, 30fps, video only, 23.11MiB
18           mp4        640x360    360p  139k , avc1.42001E, 30fps, mp4a.40.2 (44100Hz) (best)