Call progress_bar as a asynchronous co-routine

[blakeca00]

Progress bar functionality currently a hardcoded delay routine waiting for valid login using new keyset to authenticate.

Progress bar should be called by an asyncio coroutine that yields to authenticated() module function in cli.py.

When authenicated() returns True; ie, auth occurs with the new credentials, the program can exit progress_bar permanently.

This enhancement has the benefit of shortening the waiting time for key rotation process while completely eliminating the chance of a failed rotation.

[blakeca00]

progress bar must be blocking; is the primary reason its functionality exists (graphic is symptomatic benefit only) --- won't fix.