Create a new client lib for Bugzilla

[suhaibmujahid]

Similar to #6306, see #6179

Even though libmozdata is maintained and widely used across our tools, I think we need a more modern library that offers:

• Type safety with proper type hints/annotations (perhaps Pydantic)
• Async support
• A clean query builder API for constructing advanced queries
• Sensible retry defaults for when Bugzilla is having bad time

Ref:

• https://github.com/jgraham/bugdantic