GeneticAlgorithm function fitness argument does not check number of inputs

[Dan-Christiansen]

The number of elements in the fitness tuple is not checked during GeneticAlgorithm function execution.

Example: when performing single objective minimization, the function is expected to work like

GeneticAlgorithm(..., fitness=(min,), ...)

But it can also work as

GeneticAlgorithm(..., fitness=('min', 'min', 'min', ...), ...)

which would be more appropriate for multi-objective.

The function will still execute and return the single objective