handle seeing current priv again after trying to escalate auth

[carlmontanari]

dont timeout when devices are not ready to escalate auth. cropped up in scrapligo/boxen when connecting to device that just fired up -- sending "enable" caused the device to say something like "cant do that yet, not ready" and kicked back to the exec prompt. scrapligo died at that point as it was looking for either the password prompt or the privilege exec prompt. this fixes that to also accept seeing the exec (or w/e the current prompt is) prompt one more time. this is fine because before moving on we validate the current prompt/priv level is what we want (before breaking out of the escalate auth loop).

[codecov]

Codecov Report

Merging #234 (8ab6cbd) into develop (036ea92) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #234   +/-   ##
========================================
  Coverage    90.49%   90.49%           
========================================
  Files           59       59           
  Lines         3449     3449           
========================================
  Hits          3121     3121           
  Misses         328      328           

Impacted Files	Coverage Δ
scrapli/driver/network/async_driver.py	96.93% <ø> (ø)
scrapli/driver/network/sync_driver.py	96.93% <ø> (ø)

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