Remove project field from IAM documentation

[muhammadpanji]

Fix: hashicorp/terraform-provider-google#7170

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[muhammadpanji]

This is related to #4662

My understanding is the resource_iam.html.markdown.erb file will include the project parameter if object.base_url contain {{project}}, which is true in

magic-modules/mmv1/products/storage/api.yaml

Line 31 in 9d0a00f

base_url: b?project={{project}}

Looking at the following iam_policy.base_url:

• magic-modules/mmv1/products/artifactregistry/api.yaml

  Line 66 in 9d0a00f

  base_url: projects/{{project}}/locations/{{location}}/repositories/{{name}}

  
  and compare it to :

• magic-modules/mmv1/products/storage/api.yaml

  Line 48 in 9d0a00f

  base_url: 'b/{{name}}'

I'm proposing changing the include comparison to use iam_policy.base_url value instead of base_url value

[slevenick]

/gcbrun

[slevenick]

I think we need a nil check on the iam policy's base_url. This is failing to build probably because the IAM policy does not always have its own base_url, and in most cases inherits from the parent object