Update YDL-UI program (Italian language/youtube-dl/ffmpeg)

[bovirus]

Describe the bug A clear and concise description of what the bug is.

Please update application with

• Updated version of YDL-UI Italian language
• Updatef version of youtube-dl.exe
• Updated version of ffmpeg.

To Reproduce Steps to reproduce the behavior (if applicable, attach preset file):

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior A clear and concise description of what you expected to happen.

Screenshots If applicable, add screenshots to help explain your problem.

Information (please complete the following information)

• YDL-UI Version: [e.g. v1.4.2]
• OS: [e.g. Windows 7]
• Architecture: [e.g. x86, x64]

Additional context Add any other context about the problem here.

[Maxstupo]

Release v2.6.6