DYN-7086 Correctly cast package search results to show updated package info

[zeusongit]

Purpose

This is fixing a regression in the master for package search.
The search results should be cast to PackageManagerSearchElementViewModel using the new method GetSearchElementViewModel to populate it's install status, this will help correctly display the package info in Package manager window.

Declarations

Check these if you believe they are true

• The codebase is in a better state after this PR
• Is documented according to the standards
• The level of testing this PR includes is appropriate
• User facing strings, if any, are extracted into *.resx files
• All tests pass using the self-service CI.
• Snapshot of UI changes, if any.
• Changes to the API follow Semantic Versioning and are documented in the API Changes document.
• This PR modifies some build requirements and the readme is updated
• This PR contains no files larger than 50 MB

Release Notes

• Correctly cast package search results to show updated package info

Reviewers

@DynamoDS/dynamo

[github-actions]

See the ticket for this pull request: https://jira.autodesk.com/browse/DYN-7086

[github-actions]

UI Smoke Tests

Test: success. 11 passed, 0 failed.
TestComplete Test Result
Workflow Run: UI Smoke Tests
Check: UI Smoke Tests - net8.0

[QilongTang]

Do we need this if condition? I thought we can just do CachedPackageList.Where(e =>e.Name.Equals(packageName)

[zeusongit]

Yep, that's what I thought when I looked at it. But I did not add this code, I just reverted this change to its previous state, thinking don't fix something that ain't broke. ;)

[zeusongit]

updated

[QilongTang]

LGTM with one question