Fix infinite loop time step rejection

[wthrowe]

Proposed changes

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Further comments

[knelli2]

@geoffrey4444 could you please try this change out on the case you found that fails? Once you approve, I'll go ahead and merge

[wthrowe]

Updated to not test the ASSERT when assertions are not enabled.

[knelli2]

@geoffrey4444 Has tested this on a BBH and confirms it works