fix: Juju v4 solution tests

[MichaelThamm]

Issue

Fix this client error in CI (ref) for Juju v4 solution tests, which only happen after the plan is calculated and the apply begins:

│ Error: Client Error
│ 
│   with module.cos-lite.juju_integration.external_traefik_certificates[0],
│   on .terraform/modules/cos-lite/terraform/cos-lite/integrations.tf line 323, in resource "juju_integration" "external_traefik_certificates":
│  323: resource "juju_integration" "external_traefik_certificates" {
│ 
│ Unable to consume remote offer, got error: application offer
│ "admin/jubilant-6cf2fc62.certificates" not found

Solution

Add a depends_on = [module.ssc] in the COS module so it deploys after the SSC module avoiding the "admin/jubilant-6cf2fc62.certificates" CMR race condition.

Checklist

• I have added or updated relevant documentation.
• PR title makes an appropriate release note and follows conventional commits syntax.
• Merge target is the correct branch, and relevant tandem backport PRs opened.
• This PR has Terraform product changes and appropriate lifecycle args and moved blocks were added to the terraform/*/upgrades.tf file(s).
• This PR has breaking changes to the product API(s) and I have created an issue in SolQA pipelines to address this.

Context

Testing Instructions

I had to SSH into the runner and apply the plan again to get it to work. This indicates that the Terraform plan is racy.
terraform apply -var="ca_model=jubilant-83df6aa0" -var="cos_model=jubilant-39d9ca92" -var="s3_endpoint=http://10.151.33.252:8080" -var="s3_secret_key=secret-ke y" -var="s3_access_key=access-key":

Apply complete! Resources: 3 added, 0 changed, 0 destroyed.

Upgrade Notes