cli: remove pexpect dependency

GetKeyCommand is a deprecated POC that no longer maintained/supported,
since pexpect was forked in latest fedora, and this is only pexpect owner,
this patch removes both GetKeyCommand and pexpect/pexpect-u dependency.

Change-Id: Ief144fc7f32844a08463a497f2b483703d6ec0d3
Signed-off-by: Michael pasternak <mpastern@redhat.com>