Fix typos in unit descriptions [skip ci]
Fix typos in unit descriptions [skip ci]

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