Refactor tests to use `createAlert` part 1

What does this MR do and why?

app/assets/javascripts/filtered_search/visual_token_value.js and app/assets/javascripts/filtered_searc h/filtered_search_manager.js were migrated to use createAlert in !98949 (merged).

However, the test were not updated to use createAlert because they didn't failed. The reason for that is because the test were asserted to not be invoked.

Part of Bulk replacement of `createFlash` by `createAlert` (#366396 - closed)

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How to set up and validate locally

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