keystore_cli_v2 --prompt_text expects a UTF-8 string

The argument --prompt_text was parsed as an ASCII string which does not
reflect the aspired featrue set.

Also fixes a typo in an error message

Bug: 74806224
Test: manually tested
Change-Id: Ie534ea03fbe36b74c9584647b52b50f852e7dbb3
1 file changed