Make sure test for unique=True tests duplicate keyword
Make sure test for unique=True tests duplicate keyword

saimn/astropy,astropy/astropy,joergdietrich/astropy,joergdietrich/astropy,DougBurke/astropy,StuartLittlefair/astropy,tbabej/astropy,kelle/astropy,stargaser/astropy,aleksandr-bakanov/astropy,dhomeier/astropy,lpsinger/astropy,mhvk/astropy,dhomeier/astropy,bsipocz/astropy,bsipocz/astropy,kelle/astropy,bsipocz/astropy,MSeifert04/astropy,tbabej/astropy,tbabej/astropy,larrybradley/astropy,larrybradley/astropy,mhvk/astropy,StuartLittlefair/astropy,lpsinger/astropy,StuartLittlefair/astropy,funbaker/astropy,funbaker/astropy,DougBurke/astropy,pllim/astropy,AustereCuriosity/astropy,StuartLittlefair/astropy,kelle/astropy,joergdietrich/astropy,pllim/astropy,lpsinger/astropy,saimn/astropy,larrybradley/astropy,tbabej/astropy,dhomeier/astropy,MSeifert04/astropy,AustereCuriosity/astropy,pllim/astropy,funbaker/astropy,tbabej/astropy,aleksandr-bakanov/astropy,lpsinger/astropy,mhvk/astropy,pllim/astropy,pllim/astropy,dhomeier/astropy,stargaser/astropy,AustereCuriosity/astropy,saimn/astropy,bsipocz/astropy,astropy/astropy,AustereCuriosity/astropy,DougBurke/astropy,joergdietrich/astropy,lpsinger/astropy,mhvk/astropy,astropy/astropy,stargaser/astropy,mhvk/astropy,MSeifert04/astropy,dhomeier/astropy,larrybradley/astropy,MSeifert04/astropy,funbaker/astropy,AustereCuriosity/astropy,astropy/astropy,joergdietrich/astropy,DougBurke/astropy,aleksandr-bakanov/astropy,aleksandr-bakanov/astropy,stargaser/astropy,larrybradley/astropy,astropy/astropy,kelle/astropy,kelle/astropy,saimn/astropy,saimn/astropy,StuartLittlefair/astropy