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 https://github.com/GoogleCloudPlatform/magic-modules/blob/9d0a00f2dd79ed96655a3b3e849b2789b42c8a1d/mmv1/products/storage/api.yaml#L31

Looking at the following iam_policy.base_url:

• https://github.com/GoogleCloudPlatform/magic-modules/blob/9d0a00f2dd79ed96655a3b3e849b2789b42c8a1d/mmv1/products/artifactregistry/api.yaml#L66 and compare it to :

• https://github.com/GoogleCloudPlatform/magic-modules/blob/9d0a00f2dd79ed96655a3b3e849b2789b42c8a1d/mmv1/products/storage/api.yaml#L48

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

[slevenick]

/gcbrun