refactor: update bapi.py

[nautics889]

Little updates in bapi.py.

My apologies for the delay.

This commit contains tiny changes of bapi.py module:

1. Adds logger to be used across bapi.py.
2. Adds catching of specific exceptions instead of general Exception, adds logging an according message with (log level DEBUG since most likely that logs would be useful only when troubleshooting).
3. Using f-strings instead of string concatination (AFAIK the package support only 3.7+).

This PR does not affect behavior of the code (except adding some new log-records).

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• (feat): add basic logger in bapi.py
• (refactor): catch specific exceptions instead of the general one when requesting real addr in bapi.py
• (refactor) use f-string instead of string concat (since the package supports only py 3.7+)

[upbit]

Thanks for contribution! Using logger is better than ignoring all errors as before. Merged!