issue when use googlecompute-export function.

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#### Overview of the Issue

latest package

#### Reproduction Steps

use packer to create gcp image and export image to bucket.

post-processor "googlecompute-export" {
paths = [
"${var.gcp_image_bucket_package_uri}.tar.gz",
]
keep_input_artifact = true
}
}

error are followings :

==> cloudbackup.googlecompute.ubuntu: Running post-processor: (type googlecompute-export)
==> cloudbackup.googlecompute.ubuntu (googlecompute-export): Exporting image cloudbackup-image-june2025-202505200001 to destination: [gs://cloudbackup_imagestore/june2025/cloudbackup-image-june2025-202505200001.tar.gz]
==> cloudbackup.googlecompute.ubuntu (googlecompute-export): Creating temporary RSA SSH key for instance...
==> cloudbackup.googlecompute.ubuntu (googlecompute-export): Using image: debian-12-worker-v20250513
==> cloudbackup.googlecompute.ubuntu (googlecompute-export): Creating instance...
cloudbackup.googlecompute.ubuntu (googlecompute-export): Loading zone: asia-southeast1-a
==> cloudbackup.googlecompute.ubuntu (googlecompute-export): Error creating instance: googleapi: Error 403: Required 'compute.zones.get' permission for 'projects/devops-xxxx-xxxx/zones/asia-southeast1-a', forbidden
Build 'cloudbackup.googlecompute.ubuntu' finished after 4 minutes 14 seconds.

for the service account I used, already has Compute.Admin and Compute Viewer permission.

### Plugin and Packer version

From `packer version`
packer --version 1.9.1

required_plugins {
googlecompute = {
source = "github.com/hashicorp/googlecompute"
version = "= 1.1.9"
}