## Is your feature request related to a problem?

Currently if you login with SAML and you don't have an account on the PostHog instance one of two things happen: a) either a new account is created **if the email matches the domain whitelist** or b) you get turned down at the door. Yet after some thought, the point of SAML is that you manage user provisioning in a separate centralized system, so we shouldn't have the extra domain check. 

## Describe the solution you'd like

If a user logins through SAML and their account doesn't exist, create it automatically, regardless of whether it matches the domain whitelist.


## Describe alternatives you've considered

Keeping as is.

## Additional context

There's a complicating factor which is that SAML login is instance-based yet user signup is organization-based, so there's the edge case of an instance having multiple orgs. Should the user then be signed up to all organizations?

#### *Thank you* for your feature request – we love each and every one!

ee/api/test/test_authentication.py
settings = cast(Dict, copy.deepcopy(MOCK_SETTINGS))
        settings["SOCIAL_AUTH_SAML_ENABLED_IDPS"]["posthog_custom"][
            "x509cert"
        ] = """MIIDPjCCAiYCCQC864/0fftWQTANBgkqhkiG9w0BAQsFADBhMQswCQYDVQQGEwJV
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