Removed FIXME statements for effective_lower_bound
Call cobrapy add_reactions before cameo specific code
Fixed reference heuristic results (reaction_knockout_single_objective.pkl was even empty!) necessary due to now correctly working get_primal_by_id
Updated optlang SHA (541273d0fcbe59f8922943ce9b8c2ad7d94c18dc)
Skip heuristic strain design tests as they're not deterministic when seeded