chore: check runtime errors

[Rich-Harris]

Currently, if we encounter an error while running a test, we check that it matches the expected runtime_error. But we don't check that an error occurred, if runtime_error is set. This fixes that, and removes a test that of a thing that no longer fails post #9739

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• Run the tests with pnpm test and lint the project with pnpm lint

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Latest commit: 539ebe2

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