LG-763 Fix SAML NameFormat to comply with the SAML 2.0 standard

[stevegsa]

Why: So agencies can interface to our SAML implementation out of the box and not have to customize code to our specific SAML implementation.

How: Update nameformat to be 'urn:oasis:names:tc:SAML:2.0:attrname-format:basic' (simple string value) when we send back a UUID or email.

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[monfresh]

LGTM. Is this going to break existing SAML integrations?

[stevegsa]

@monfresh It might. We have to coordinate with them and do some testing in int.