enh(test): add test for nested model create within update query
enh(test): add test for nested model create within update query

ctartist621/waterline,antoniopol06/waterline,dmarcelino/waterline,jonniedeb/waterline,waterlinejs/waterline,contra/waterline,citizenken/waterline,kriswill/waterline,Zaggen/waterline,tjwebb/waterline,balderdashy/waterline,scippio/waterline,hippich/waterline,mmiller42/waterline,atiertant/offshore,Atlantis-Software/offshore,jianpingw/waterline,3032441712/waterline,luislobo/waterline,metidia/waterline,particlebanana/waterline,AlexisNo/waterline,Atlantis-Software/waterline,moklick/waterline,mcanthony/waterline,listepo/waterline