...with `assertHasRedbox` and `assertNoRedbox`.
`hasRedbox()` has a hardcoded timeout of 5s that is only required for
the negative assertion.
Instead, we now have dedicated assertions for the positive
(`assertHasRedbox`) and negative case (`assertNoRedbox`).
The negative assertion still has the hardcoded timeout.
But the positive assertion just retries until we find the Redbox.
This speeds up tests using the positive assertion.
Removing `hasRedbox` also uncovered some unused expressions e.g. `await
hasRedbox(browser)`.
These expressions probably wanted to use `expect(await
hasRedbox(browser)).toBe(true)
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