google_sql_database_instance documentation advanced_machine_features incorrect

[pdewilde]

Tested GCP Provider Version: 4.68.0

Bug introduced in Version: 4.66.0

There is a mistake in the documentation for the google_sql_database_instance documentation.

The advanced_machine_type subblock is shown to have many fields including availability_type, but in reality, only threads_per_core is supposed to be in the sub-block, and others are not within it. https://github.com/hashicorp/terraform-provider-google/blob/release-4.68.0/google/resource_sql_database_instance.go#L158

The documentation should be updated to correctly show the location of the settings not in the advanced_machine_features block. Currently versions 4.66.0-4.68.0 seem to be affected.

[pdewilde]

Caused by #14604

[edwardmedia]

b/285939652