leapp should warn of bad type used in dialog\answerfile

[fernflower]

Currently it is possible to pass a non-boolean type to a BooleanComponent in a dialog via answerfile and absolutely no warning\report message is shown. How the value will be treated is up to the actor's
logic to decide. I suggest we add some transparency and reporting to the matter.

leapp answer --section remove_pam_pkcs11_module_check.confirm=shouldbeaboolhere

[remove_pam_pkcs11_module_check]
confirm = shouldbeaboolhere

Actual usage behavior is defined by the actor https://github.com/oamg/leapp-repository/blob/master/repos/system_upgrade/el7toel8/actors/removeoldpammodulescheck/actor.py#L62