Bump yt-dlp from 2025.5.22 to 2025.7.21

Bumps [yt-dlp](https://github.com/yt-dlp/yt-dlp) from 2025.5.22 to 2025.7.21.
- [Release notes](https://github.com/yt-dlp/yt-dlp/releases)
- [Changelog](https://github.com/yt-dlp/yt-dlp/blob/master/Changelog.md)
- [Commits](https://github.com/yt-dlp/yt-dlp/compare/2025.05.22...2025.07.21)

---
updated-dependencies:
- dependency-name: yt-dlp
  dependency-version: 2025.7.21
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -18,4 +18,4 @@ torch==2.7.0
 transformers==4.52.4
 ffmpeg-python==0.2.0
 elevenlabs==1.57.0
-yt-dlp==2025.5.22
+yt-dlp==2025.7.21