How can I set `grant type` when using `google_identity_platform_oauth_idp_config` in terraform?

I am using google_identity_platform_oauth_idp_config in terraform to deploy identity to GCP. I have read this doc: https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/identity_platform_oauth_idp_config but I can't find where I can set the grant type.

By default it set it to Implicit flow. How can I set it to Code flow?

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