Avoid map key conflict for document results (#456)

* Avoid map key conflict for document results

We currently can't have VerticalResults for document verticals since
two results from the same entity will cause a map key conflict.
To resolve this, we are making the key the result ID and the result
index which should always be unique.

J=WAT-4282
TEST=manual,auto

Created a test document search config on the test-site which previously
failed to return VerticalResults properly due to the key error
now returns the results and updates on a new search

* Update snapshots

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Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

src/components/VerticalResultsDisplay.tsx

@@ -56,5 +56,6 @@ function renderResult<T>(
   CardComponent: CardComponent<T>,
   result: Result<T>
 ): JSX.Element {
-  return <CardComponent result={result} key={result.id || result.index}/>;
+  const key = result.id && result.index ? `${result.id}-${result.index}` : result.id || result.index;
+  return <CardComponent result={result} key={key}/>;
 }