Improve documentation on the connection resource options fields

[sergiught]

Checklist

• I agree to the terms within the Auth0 Code of Conduct.

Describe the problem you'd like to have solved

The current auth0_connection resource is used to manage all different types of connections. These however have differed allowed fields on the options block.

Describe the ideal solution

To make it clearer to developers using this resource we should improve the documentation to clearly state which options are allowed for which connection type (strategy).

Alternatives and current workarounds

No response

Additional context

• See also Separate auth0_connection options blocks into provider-specific option blocks #234

[sergiught]

Closing this down as this is now available in the latest release: https://registry.terraform.io/providers/auth0/auth0/latest/docs/resources/connection.