[RFC] Deprecate support for the TestTube logger

[ananthsub]

Proposed refactoring or deprecation

Motivation

This logger is not actively maintained: https://github.com/williamFalcon/test-tube
This came up during the discussion of API improvements we can make to the Lightning Logger interace: #9004

The TestTube logger is the only logger which supports close - this is likely an artifact from the early days of Lightning. Are there currently users of this logger? @edenafek ?

Side-effect of #7740 and https://docs.google.com/document/d/1xHU7-iQSpp9KJTjI3As2EM0mfNHHr37WZYpDpwLkivA/edit

If the library isn't actively maintained, deprecating & removing this support means:

• Simplified options for users as to what loggers the framework provides
• Reduced framework maintenance cost (tests, dependencies)

Pitch

Deprecate support for test tube if it's not actively maintained.

cc @edward-io

Additional context

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