be more verbose when enabling/disabling oauth providers

[dbarrosop]

Since we moved to grant one of three things can happen:

1. If a provider is disabled and you visit /signin/provider/$disabledprovider hasura-auth will go to the redirect url with the query arg ?error=disabled-endpoint&errorDescription=This+endpoint+is+disabled.
2. If a provider is enabled and configured, everything follows the expected workflow
3. If a provider is enabled but misconfigured in some way, a 404 is returned when visitin /signin/provider/$disabledprovider.

Ideally we would:

• On startup log which providers are being enabled
• If there is an issue with a provider, be clear about it on the logs
• When visiting /signin/provider/$misconfigured-provider log there is an issue on the logs and go to the redirect url with something like ?error=misconfigured-provider&errorDescription=This+provider+is+misconfigured

[stale[bot]]

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