[BUG] rancher2_cluster_v2 resources intermittently fail to provision downstream clusters with cluster_v1_id is empty error

[Josh-Diamond]

Rancher Server Setup

• Rancher version: v2.9, v2.10
• Installation option (Docker install/Helm Chart): Helm

Information about the Cluster

• Kubernetes version: 1.30.6+rke2r1 + v1.31.2+rke2r1
• Cluster Type (Local/Downstream): Downstream - affects RKE2 + K3s

User Information

• What is the role of the user logged in? Admin

Provider Information

• What is the version of the Rancher v2 Terraform Provider in use? v5.2.0 and v6.0.0

Describe the bug

Intermittently, downstream clusters fail to come up when attempting to provision downstream rancher2_cluster_v2 resource

To Reproduce

1. Intermittently hit when provisioning rancher2_cluster_v2 resource - (hit more commonly with RKE2)

Actual Result

Setting cluster V2 legacy data: cluster_v1_id is empty

Screenshots:

Expected Result

Cluster provisions successfully and doesn't error out due to a computed resource being empty