terraform-provider-azurerm: Updating an `azurerm_automation_runbook` causes subsequent `terraform apply` to want to recreate the associated `azurerm_automation_job_schedule`

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Terraform 0.13.3 and AzureRM Provider Version 2.24.0

Current providers:

- Using previously-installed hashicorp/time v0.5.0
- Using previously-installed hashicorp/tls v2.2.0
- Using previously-installed hashicorp/azurerm v2.24.0
- Using previously-installed hashicorp/azuread v0.11.0
- Using previously-installed hashicorp/random v2.3.0
- Using previously-installed hashicorp/null v2.1.2
- Using previously-installed hashicorp/external v1.2.0
- Using previously-installed hashicorp/local v1.4.0

Affected Resource(s)

• azurerm_automation_job_schedule
• azurerm_automation_runbook

Terraform Configuration Files

data "local_file" "sync_group_roles" {
  filename = "${path.module}/runbooks/sync-group-roles.ps1"
}

resource "azurerm_automation_runbook" "sync_group_roles" {
  name        = "Sync-Group-Roles"
  description = "Ensure members of Groups have the appropriate AD roles, since roles cannot be assigned to Groups."

  automation_account_name = azurerm_automation_account.account.name
  resource_group_name     = azurerm_resource_group.automation.name
  location                = azurerm_resource_group.automation.location

  runbook_type = "PowerShell"
  log_progress = false
  log_verbose  = false

  content = data.local_file.sync_group_roles.content

  tags = {
    "team" = local.automation_responsible_team
  }

  depends_on = [
    azurerm_automation_module.az_accounts,
    azurerm_automation_module.azuread,
    azurerm_automation_module.az_resources,
  ]
}

resource "azurerm_automation_schedule" "daily_ad_sync" {
  name = "Daily AD roles sync"

  automation_account_name = azurerm_automation_account.account.name
  resource_group_name     = azurerm_resource_group.automation.name

  frequency  = "Day"
  interval   = 1
  timezone   = local.timezone
  start_time = "${local.date_tomorrow}T07:00:00${data.external.timezone_offset.result["offset"]}"

  # Just making it explicit but from the documentation the start_time is only used on create.
  lifecycle {
    ignore_changes = [start_time]
  }
}

resource "azurerm_automation_job_schedule" "sync_group_roles" {
  automation_account_name = azurerm_automation_account.account.name
  resource_group_name     = azurerm_resource_group.automation.name

  schedule_name = azurerm_automation_schedule.daily_ad_sync.name
  runbook_name  = azurerm_automation_runbook.sync_group_roles.name
}

Expected Behavior

After an update on azurerm_automation_runbook no changes other than the runbook are done even on subsequent terraform apply

Actual Behavior

terraform apply after updating azurerm_automation_runbook

  # module.automation.azurerm_automation_job_schedule.sync_group_roles will be created
  + resource "azurerm_automation_job_schedule" "sync_group_roles" {
      + automation_account_name = "devops-automation"
      + id                      = (known after apply)
      + job_schedule_id         = (known after apply)
      + resource_group_name     = "AutomationRG"
      + runbook_name            = "Sync-Group-Roles"
      + schedule_name           = "Daily AD roles sync"
    }

Steps to Reproduce

1. Update configuration and/or content of azurerm_automation_runbook resource
2. terraform apply to update the runbook
3. terraform plan or terraform apply will now show that azurerm_automation_job_schedule needs be created.

References

This seems to be the exact same issue as #7130 which is supposed to be fixed in v2.21.0