fix: Account for upcoming init error message change

[radeksimko]

This is to address the following nightly test failure:

    util_test.go:113: [INFO] running Terraform command: /tmp/tfinstall756103370/gitref-refs-heads-main/terraform470134907 show -json -no-color
    show_test.go:90: expected error ErrNoInit, got *fmt.wrapError: exit status 1
        
        Error: Inconsistent dependency lock file
        
        The following dependency selections recorded in the lock file are
        inconsistent with the current configuration:
          - provider registry.terraform.io/hashicorp/null: required by this configuration but no version is selected
        
        To make the initial dependency selections that will initialize the dependency
        lock file, run:
          terraform init
        
--- FAIL: TestShow_errInitRequired (0.12s)
    --- FAIL: TestShow_errInitRequired/basic-refs/heads/main (0.12s)