N_events specified in fit_single should throw error if the number of events in provided magnitudes or parameters is different

[GWeindel]

When providing a number of events to be estimate in fir_single() the dimension in the (eventual) provided magnitudes determines the number of events to be fitted instead of the n_events parameter. Having inconsistency between required number of events and provided magnitudes should throw an error instead of estimating N event based on the dimension of the magnitudes