Fix Graph unit tests conflicting with global mock

[yuseok89]

CI is currently broken on main due to failures in Graph.test.tsx, which blocks all in-flight PRs. This is a minimal fix to unblock CI: useGridTiSummariesStream is never invoked because the global Graph mock in testsSetup.ts replaces the real component, so this change calls vi.unmock in that single test file.

If we would prefer to avoid vi.unmock here, possible directions include extracting the tested logic into a hook or narrowing the scope of the global Graph mock in testsSetup.ts.

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[yuseok89]

Duplicate of #65555