Issue Summary: Customer has configured Single Sign-On (SSO) using their own Identity Provider (IdP). However, on their customer portal login page, both the "SSO" and "Sign up with Password" options are visible. This is causing confusion among their users, as they expect only the SSO option to be available.

Steps to Reproduce

1. Navigate to the customer portal: https://comatic.atlassian.net/servicedesk/customer/portal/5
2. Enter an email address.
3. Observe that the option to "Sign up with Password" is displayed alongside the SSO login option. (Screenshot attached)

Expected Results: 

• Customers who have enforced SSO should only see the SSO login option.
• The "Sign up with Password" option should be hidden to prevent user confusion.

Actual Results: The "Sign up with Password" option is still visible despite SSO being enabled.  

I asked the customer to follow the below steps: 

1. Go to your site and click on the gear (settings) icon at the top-right corner.
2. Select Products from the menu.
3. Under Jira Service Management, click on Authentication.
4. Locate the Password section and disable the option for Login with email and password.

But this is not suitable in this scenario, the problem with that solution is, that as soon as customer activate this option, no one will be able to send e-mails to the portal which are not already signed up in IDP. 

Workaround: No current workaround is available.