fix: software artifacts are downloaded twice when the update-list feature is not available

[Ruadhri17]

This small PR fixes issue with software artifacts being downloaded twice when update-list is not available. Extra validation step was introduced to check if artifact is downloaded.

Proposed changes

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (general improvements like code refactoring that doesn't explicitly fix a bug or add any new functionality)
• Documentation Update (if none of the other choices apply)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Paste Link to the issue

• Software updates are downloaded multiple times when update-list isn't supported by the relevant plugin #3062

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA (in all commits with git commit -s)
• I ran cargo fmt as mentioned in CODING_GUIDELINES
• I used cargo clippy as mentioned in CODING_GUIDELINES
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.

Files	Patch %	Lines
crates/core/plugin_sm/src/plugin.rs	0.00%	4 Missing ⚠️

Additional details and impacted files

📢 Thoughts on this report? Let us know!

[github-actions]

Robot Results

✅ Passed	❌ Failed	⏭️ Skipped	Total	Pass %	⏱️ Duration
492	0	2	492	100	1h22m14.571546s

[albinsuresh]

LGTM. Can a system test be added to fully confirm the effectiveness of the fix? You can just assert that the agent log contains only one "downloading" statement for that artefact.

[didier-wenzek]

I would only log an info! telling that the agent installs the packages one after the other as update_list is not supported for this type of packages

[jarhodes314]

Suggested change

	if let Err(SoftwareError::UpdateListNotSupported(name)) = outcome {
	info!("{}", SoftwareError::UpdateListNotSupported(name));
	if let Err(err @ SoftwareError::UpdateListNotSupported(_)) = outcome {
	info!("{err}");

[rina23q]

Thanks, applied

[didier-wenzek]

Approved

[gligorisaev]

LGTM