Merge pull request #325371 from mweinelt/youtube-dl

youtube-dl: mark as vulnerable

pkgs/tools/misc/youtube-dl/default.nix

···
     maintainers = with maintainers; [ bluescreen303 fpletz ];
     platforms = with platforms; linux ++ darwin;
     mainProgram = "youtube-dl";
+    knownVulnerabilities = [
+      "youtube-dl is unmaintained, migrate to yt-dlp, if possible"
+    ];
   };
 }