Pydub dependency raises warnings

[EnjoyBacon7]

Pydub (required by a dependency) has an unresolved issue pertaining to a SyntaxWarning. As this does not affect OpenRAG functionnally, the warnings should be suppressed voluntarily for clarity. The Pydub issue is discussed here in more detail. Other projects have already gone this route, like pipecat.

In our case, this adds these warnings on startup:

(DocSerializer pid=609) /app/.venv/lib/python3.12/site-packages/pydub/utils.py:300: SyntaxWarning: invalid escape sequence '\('
(DocSerializer pid=609)   m = re.match('([su]([0-9]{1,2})p?) \(([0-9]{1,2}) bit\)$', token)
(DocSerializer pid=609) /app/.venv/lib/python3.12/site-packages/pydub/utils.py:301: SyntaxWarning: invalid escape sequence '\('
(DocSerializer pid=609)   m2 = re.match('([su]([0-9]{1,2})p?)( \(default\))?$', token)
(DocSerializer pid=609) /app/.venv/lib/python3.12/site-packages/pydub/utils.py:310: SyntaxWarning: invalid escape sequence '\('
(DocSerializer pid=609)   elif re.match('(flt)p?( \(default\))?$', token):
(DocSerializer pid=609) /app/.venv/lib/python3.12/site-packages/pydub/utils.py:314: SyntaxWarning: invalid escape sequence '\('
(DocSerializer pid=609)   elif re.match('(dbl)p?( \(default\))?$', token):