Add console command to disable SAML logins

[jerm]

If a Snipe-IT sire has SAML enabled, and the SAML config is sufficiently
borked, login and logout pages will 500. That's probably
something that should be examined, but in the meantime, it'd be handy to
not have to manually edit the database to turn off SAML in order to
recover the site.

In this commit, I'm creating a saml-disable console command. And by
create, i mean i'm copypasta-ing the existing ldap-disable command.

[what-the-diff]

PR Summary

• Introduction of a New Comand to Disable SAML Settings
  A new command has been added to the software. This command allows you to turn off SAML settings within the application, essentially disabling a method used for exchanging authentication and authorization data.

• Definition of Command Signature and Description
  The new command comes with an appropriate signature, which is snipeit:saml-disable. This unique signature helps to identify the command and its function. It is accompanied by a description that gives additional details about what it does.

• Inclusion of a Confirmation Prompt
  To guard against unintended outcomes, a confirmation prompt has been implemented. This feature will prevent the accidental disabling of SAML support by asking users for confirmation before proceeding with the command.

• Command Acting on User's Confirmation
  Upon receiving a positive confirmation from the user, the command executes and updates the settings to disable SAML. It then gives feedback, informing the user of the success or failure of the operation.