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Translate username, password and database from UTF8 into desired charset,
if  non-auto default-character-set was used, on Windows10 1903

This change is implemented only in the command line client, and mainly to
allow users with non-UTF8 passwords to login.

The user is supposed to use the same charset that was used during setting
password (usually, console CP if used in CLI)

Add a test to document the behavior.