added test functions for `welch_cohere()`
added test functions for `welch_cohere()`

neuroelectro/elephant,Junji110/elephant,carloscanova/elephant,alperyeg/elephant,dholstein/elephant,espenhgn/elephant,NeuralEnsemble/elephant,mdenker/elephant,espenhgn/elephant,INM-6/elephant,NeuralEnsemble/elephant,etorre/elephant,etorre/elephant,mdenker/elephant,alperyeg/elephant,NeuralEnsemble/elephant,ccluri/elephant,INM-6/elephant,pietroquaglio/elephant,dholstein/elephant,apdavison/elephant,pietroquaglio/elephant,btel/elephant,INM-6/elephant,ccluri/elephant,JuliaSprenger/elephant,carloscanova/elephant,neuroelectro/elephant,btel/elephant,mdenker/elephant,apdavison/elephant,Junji110/elephant