This PR finalizes the frontend changes related to PR #1225. The custom result index query now uses an index pattern instead of a single index.

Additionally, this PR addresses an issue where missing custom result indices would appear because the original code checked for the existence of an index name, but now we use it as a prefix. We have updated the logic to perform a prefix search instead of checking for index name equality.

This PR also resolves issue opensearch-project#765 by downgrading the version of jest-canvas-mock.

Testing Done:
* Added unit tests.
* Verified that the custom result index missing callout is not shown.
* Confirmed that the frontend can still display old and new results after a rollover.

Signed-off-by: Kaituo Li <kaituo@amazon.com>

Signed-off-by: Kaituo Li <kaituo@amazon.com>

Signed-off-by: Kaituo Li <kaituo@amazon.com>