The import VM tasks step is shown as ConvertingInstance while its still exporting from vcenter

### problem

The import VM tasks step is shown as ConvertingInstance while its still exporting from vcenter. It needs to show in UI,API the correct step i.e exporting the instance/OVF.

### versions

4.22.0

### The steps to reproduce the bug

1. Import VM from external vCenter
2. Compare the import vm tasks, steps, and actuals in vCenter.

### What to do about it?

Steps should match the actuals.

重現一次從外部 vCenter 執行的匯入，並將 UI 和 API 中匯入 VM 工作的步驟與實際的 vCenter 操作進行比較。只有當匯出階段顯示為正在匯出執行個體/OVF，而不是 ConvertingInstance 時，這項工作才算完成。

由索引模型根據 Issue 內容生成。