Fix unit tests of DependencyResolver.
Fix unit tests of DependencyResolver.

grogancolin/dub,dreamsxin/dub,y12uc231/dub,xentec/dub,rjframe/dub,jeanbaptistelab/dub,alexeibs/dub,Geod24/dub,jelmansouri/dub,Abscissa/dub-data-mod,schuetzm/dub,Flamaros/dub,Abscissa/dub,p0nce/dub,nazriel/dub,D-Programming-Language/dub,gedaiu/dub