linstor: Use template's uuid if pool's downloadPath is null as resour…

[ghernadi]

Description

My colleague, @rp- is on vacation right now and we found a bug where the previously non-null VMTemplateStoragePoolVO#getLocalDownloadPath for some reason returns null in the recent versions of Cloudstack. This is my attempt to patch the issue, which worked in our test-setup.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)
• build/CI
• test (unit or integration test code)

Feature/Enhancement Scale or Bug Severity

Feature/Enhancement Scale

• Major
• Minor

Bug Severity

• BLOCKER
• Critical
• Major
• Minor
• Trivial

Screenshots (if appropriate):

How Has This Been Tested?

The following scenario no longer works without this patch:

• Create a new VM (instance)
• Stop VM and make a snapshot of it
• Create a template from the just created snapshot
• Create a new VM from the new template

The last step causes the cloud-plugin-storage-volume-linstor to try to clone from cs-null instead of cs-${template_uuid}. cs-null obviously does not exist within LINSTOR itself, which causes an error.

How did you try to break this feature and the system with this change?

[boring-cyborg]

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