feat(anta.tests): Add VerifyMgmtIdleTimeout to security tests
Adds VerifyMgmtIdleTimeout to anta/tests/security.py to verify that
management console and SSH idle-timeout are both configured and do not
exceed a configurable maximum (default 10 minutes).
Parses text output of `show management console` for the Timeout line
and `show management ssh` for the SSH idle connection timeout line.
Fails independently for each interface if the timeout is absent or
exceeds the allowed maximum.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>