GCP bootstrapping failing with validation error 'public-key is invalid'

• VM-Series bootstrap failing on GCP due to validation error and commit fails.
• Deployment is done using the Terraform script.
• In bootstrap.xml, this public-key is not configured anywhere.
• Validation error related to the error: 'public-key is invalid'

Commit Error:

Warnings:
Details:Validation Error:
mgt-config -> users -> admin -> public-key 'ZWNkc2Etc2hhMi1uaXN0cDI1NiBBQUFBRTJW...' 
is invalid. Invalid public key format
mgt-config -> users -> admin -> public-key is invalid
Commit failed

mp/ms.log

Error:  pan_schema_verify_node_constraints(pan_schema_types.c:472): 'ZWNkc2Etc2hhMi1uaXN0cDI1NiBBQUFBRTJWalpIT...'
Error:  _pan_schema_verify_node(pan_schema_obj.c:6399): is invalid , node: public-key near line 12
Error:  pan_cfg_verify_ex(pan_cfg_commit_handler.c:2324): invalid configuration. Schema verification failed.

• Platform: VM-Series on GCP
• PAN-OS / Plugin Version: Any
• Deployment: New using Terraform

// Adding METADATA Key Value pairs to VM-Series
  metadata {
    // init-config.txt will perform interface swap of VM-series on bootstrap

    vmseries-bootstrap-gce-storagebucket = "${var.fw-bootstrap-bucket}"
    serial-port-enable                   = true

    sshKeys                              = "${var.pan-public-key}"
  }

1. Change main.tf terraform script used to deploy firewalls.
2. Replace the sshKeys with ssh-keys in the VM-Series metadata field under 'resource "google_compute_instance" "firewall" '.
3. The script should be in a similar format as below:

// Adding METADATA Key Value pairs to VM-Series
metadata {
// init-config.txt will perform interface swap of VM-series on bootstrap

vmseries-bootstrap-gce-storagebucket = "${var.fw-bootstrap-bucket}"
serial-port-enable = true

ssh-keys = "${var.pan-public-key}"
}