Default systemVM template is not downloaded to S3 secondary storage

##### ISSUE TYPE

* Bug Report

##### COMPONENT NAME

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S3 Secondary storage, system VM template
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##### CLOUDSTACK VERSION

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4.19 with PR #8986
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##### CONFIGURATION

MinIO S3 bucket configured
NFS staging storage

##### SUMMARY

Although the S3 secondary storage gets added with the fix in #8986 the default system VM template do not get downloaded. In the management server logs, I can see the _'DownloadProgressCommand'_ running but the file is not being downloaded. Note that the zone is created fresh and there is no SSVM to download the template. I am assuming there may be something missing to copy the systemVM template in the management server to the S3 bucket either via staging NFS or without it.

##### STEPS TO REPRODUCE

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1. Create a MinIO S3 bucket
2. Add a zone with S3 secondary storage and NFS staging storage using the above bucket.
3. Launch the zone and wait for the system VM template status to become 'Ready'
~~~

##### EXPECTED RESULTS

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SystemVM template is downloaded
~~~

##### ACTUAL RESULTS

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SystemVM template is not downloaded
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按照描述，使用 MinIO S3 bucket、NFS 暂存存储和一个全新的 zone 重现该问题，然后查看 PR #8986 和已打开的 PR #12426。完成的标准是：启动 zone 后，默认的 SystemVM 模板能够到达 S3 次级存储并变为 Ready。

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