Verify SAML Configuration - Demo for merge request review

Demo for reviewers of https://gitlab.com/gitlab-org/....gitlab/merge_request to suggest improvements.

Improves "Test SAML SSO" button by actively verifying the configuration and displaying useful information from the SAML Response.

- Bypasses sign-in and account linking and returns the user direct to a results section of the settings page.
- Stores the full SAMLResponse in Redis and then shows this in the UI with indentation, highlighting and a "Copy" button for sharing it with support.
- Highlights important sections of the response via disabled inputs above the XML area. Displays NameID Format and shows an inline validation error if it isn't the recommended value. Displays the NameID and includes an error if it is blank or if it does not match the value linked to the current user.
- Displays all ruby-saml validation errors at the top of the new section. Before only the first error could be captured as this raised an exception.

• Category

  How-to & Style