Fix create-react-admin does not ignore auth-provider when specified and using supabase

[djhi]

Problem

When specifying supabase as the --data-provider option and local as the --auth-provider option, create-react-admin says it will ignore the --auth-provider but actually doesn't.

How To Test

• make build-create-react-admin install
• /node_modules/.bin/create-react-admin myadmin --data-provider supabase --auth-provider local
• check that the CLI does not mention anything about how to use the local auth provider
• check that the generated app does not include a custom auth provider

Additional Checks

• The PR targets master for a bugfix, or next for a feature

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