Misleading error message on validate when identity_endpoint is not set.

[selfscrum]

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Overview of the Issue

The parameter that is to be set is named identity_endpoint, but the error message is Missing input for argument [auth_url].

Reproduction Steps

packer validate .

Plugin and Packer version

packer v1.8.2

Simplified Packer Buildfile

source "openstack" "otc_packer_image" {
  }
  
build {
    sources = ["source.openstack.otc_packer_image"]
}

Operating system and Environment details

ubuntu 22.04

Log Fragments and crash.log files

Screen output:

Error: 5 error(s) occurred:

* Missing input for argument [auth_url]
* An image_name must be specified
* An ssh_username must be specified
  Note: some builders used to default ssh_username to "root".
* Either a source_image, a source_image_name, an external_source_image_url or source_image_filter must be specified
* A flavor must be specified

  on test.pkr.hcl line 8:
  (source code not available)