[DBAL-722] Add missing doc @return.
[DBAL-722] Add missing doc @return.

kimhemsoe/dbal,sarcher/dbal,adrienbrault/dbal,deeky666/dbal,stof/dbal,mihai-stancu/doctrine-dbal,lafourchette/dbal,stchr/dbal,AlexDpy/dbal,cassvail/dbal,vutung2311/dbal,kimhemsoe/dbal,LionwareSolutions/dbal,PowerKiKi/dbal,mariuz/dbal,stof/dbal,vutung2311/dbal,easybiblabs/dbal,webonyx/dbal,easybiblabs/dbal,AlexDpy/dbal,DHager/dbal,Tobion/dbal,LionwareSolutions/dbal,wuxu92/dbal,BenMorel/dbal,gencer/dbal,mbeccati/dbal,deeky666/dbal,doctrine/dbal,v-bartusevicius/dbal,arima-ryunosuke/dbal,lcobucci/dbal,LionwareSolutions/dbal,zeroedin-bill/dbal,nfrignani/dbal,drieschel/dbal,sarcher/dbal,lcobucci/dbal,stchr/dbal,bspeterson/dbal,v-bartusevicius/dbal,hason/dbal,Tobion/dbal,shivergard/dbal,kupishkis/dbal,mRoca/dbal,tk-s/dbal,mihai-stancu/doctrine-dbal,zeroedin-bill/dbal,doctrine/dbal,janschoenherr/dbal,BenMorel/dbal,PowerKiKi/dbal,vortgo/dbal,hason/dbal,sarcher/dbal,webonyx/dbal,mathroc/dbal,hason/dbal,mihai-stancu/dbal,adrienbrault/dbal,arima-ryunosuke/dbal,PowerKiKi/dbal,helicon-os/doctrine-dbal,mikeSimonson/dbal,mikeSimonson/dbal,mihai-stancu/dbal,mRoca/dbal,nfrignani/dbal,kupishkis/dbal,cassvail/dbal,easybiblabs/dbal,vortgo/dbal,janschoenherr/dbal,mariuz/dbal,lafourchette/dbal,DHager/dbal,mbeccati/dbal,gencer/dbal,arima-ryunosuke/dbal,bspeterson/dbal,webonyx/dbal,mariuz/dbal,shivergard/dbal,helicon-os/doctrine-dbal,mathroc/dbal,drieschel/dbal,adrienbrault/dbal,tk-s/dbal,kupishkis/dbal,wuxu92/dbal