Unable to clear out an existing value in default_audience in auth0_tenant

[alynielson]

Description
I set default_audience for an auth0_tenant resource to a url. It turned out that I needed to not set that property at all, as it was causing unexpected behavior in my application. I removed the url and set default_audience = null in the resource in main.tf. No change showed up in terraform plan, and nothing was changed in terraform apply, so the tenant's default audience remained set. I also tried removing the default_audience property altogether from the resource, and saw the same issue.

One thing to note is that when I tested changing the default_audience to a different string, i.e. "test", the value successfully appeared in the plan and was changed as expected in the apply. This issue seems to be limited to clearing out the default_audience property if it is already set. This seems similar to this issue, but I am unsure if they have the same root cause.

Terraform Version
Terraform v0.13.0
provider.auth0 v0.17.2

Affected Resource(s)
auth0_tenant

Expected Behavior
When the auth0_tenant resource has default_audience set, the value can be cleared out via terraform.

Actual Behavior
When the auth0_tenant resource has default_audience set, then deleting default_audience or setting the value to null does not change the value in the terraform resource or in the terraform state.

Steps to Reproduce
Create an auth0_tenant with a non-null value for default_audience.
Run terraform apply.
Set default_audience to null or remove it.
Run terraform plan - no changes pending
Run terraform apply - tenant's default audience is still set.

[github-actions]

This issue is stale because it has been open 30 days with no activity.
Stale issues will be closed after 5 days if no action is taken. If you
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[sergiught]

This relates to several other issues that are present within the provider and I have captured this along with the others within auth0/terraform-provider-auth0#14.

As this repo has moved over at https://github.com/auth0/terraform-provider-auth0 please open new issues over there from now on.