feat: add audio xblock

[irtazaakram]

This PR moved Audio XBlock from https://github.com/openedx/AudioXBlock

• Resolves AudioXBlock Migration #4
• Related to Consolidate Optional XBlocks public-engineering#317

The original repository is being deprecated here: openedx-unsupported/AudioXBlock#240

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.33%. Comparing base (1dfed49) to head (3ae5db1).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main       #3   +/-   ##
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  Coverage   83.33%   83.33%           
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  Files           1        1           
  Lines           6        6           
  Branches        1        1           
=======================================
  Hits            5        5           
  Partials        1        1           

Flag	Coverage Δ
unittests	83.33% <ø> (ø)

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[farhan]

@irtazaakram

How are we adding/maintaining the requirements in this repo.

Perhaps we should keep them in the same format of *.in, *.txt as doing in openedx-platform

[irtazaakram]

We can add the dependencies in pyproject.toml file here

xblocks-extra/pyproject.toml

Line 30 in 1dfed49

dependencies = [