Dashboard Library: Add basic unit test to suggested dashboards flow (#113825)

* Create unit tests for communityDashboardHelper

* Add unit test for autoMapDatasources

* Create unit test for DashboardCard

* --wip-- [skip ci]

* Fix test

* fix linting

* Add unit test to the dashboardLibraryApi

* update codeowners for dashboard library code

* fix: improve test coverage and fix failing tests

- Fix image handling tests in DashboardCard to verify actual behavior
- Fix UID filtering test in autoMapDatasources to use correct mock data
- Add test for dimThumbnail prop
- Add test for undefined inputs edge case
- All 82 tests now passing

* render function modified

* merge with template dashboard modifications. tests modified

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Co-authored-by: nmarrs <nathanielmarrs@gmail.com>
Co-authored-by: Juan Cabanas <juan.cabanas@grafana.com>

.github/CODEOWNERS

@@ -1101,6 +1101,7 @@ eslint-suppressions.json @grafanabot
 # Grafana Sharing Squad
 /public/app/features/dashboard-scene/sharing/ @grafana/sharing-squad
 /public/app/features/dashboard/components/ShareModal/ @grafana/sharing-squad
+/public/app/features/dashboard/dashgrid/DashboardLibrary/ @grafana/sharing-squad
 /public/app/features/manage-dashboards/components/SnapshotListTable.tsx @grafana/sharing-squad
 /pkg/services/dashboardsnapshots/ @grafana/sharing-squad
 /public/app/features/explore/QueryLibrary/ @grafana/sharing-squad