Update youtube.py

[jedhelmers]

I took a swing and it seems to be working with mp3. I'm kind of stunned haha. Anywho...
1.) updated youtube.py to check for 2 or 3 chars in regex

Please follow the guide below

• You will be asked some questions, please read them carefully and answer honestly
• Put an x into all the boxes [ ] relevant to your pull request (like that [x])
• Use Preview tab to see how your pull request will actually look like

---

Before submitting a pull request make sure you have:

• Searched the bugtracker for similar pull requests
• Read adding new extractor tutorial
• Read youtube-dl coding conventions and adjusted the code to meet them
• Covered the code with tests (note that PRs without tests will be REJECTED)
• Checked the code with flake8

In order to be accepted and merged into youtube-dl each piece of code must be in public domain or released under Unlicense. Check one of the following options:

• I am the original author of this code and I am willing to release it under Unlicense
• I am not the original author of this code but it is in public domain or released under Unlicense (provide reliable evidence)

What is the purpose of your pull request?

• Bug fix
• Improvement
• New extractor
• New feature

---

Description of your pull request and other information

Explanation of your pull request in arbitrary form goes here. Please make sure the description explains the purpose and effect of your pull request and is worded well enough to be understood. Provide as much context and examples as possible.

[lanegramling]

This PR is a duplicate of #30366. (That being said, this is the correct fix and it should work).

[dirkf]

a) This won't work

>>> import re
>>> re.findall(r'\d{2|3}', 'a22bc')
[]
>>> re.findall(r'\d{2|3}', 'a223bc')
[]
>>> re.findall(r'\d{2,}', 'a223bc')
['223']
>>> 

b) @lanegramling already submitted a working PR for this issue and @dstfw merged it.