Fix category not change (updating feed on MySQL)
Fix category not change (updating feed on MySQL)

See https://github.com/marienfressinaud/FreshRSS/issues/646

Dolomich/FreshRSS,romibi/FreshRSS,marienfressinaud/FreshRSS,aledeg/FreshRSS,romibi/FreshRSS,superboum/FreshRSS,samuelstein/FreshRSS,samuelstein/FreshRSS,aledeg/FreshRSS,samuelstein/FreshRSS,Dolomich/FreshRSS,asmundg/FreshRSS,romibi/FreshRSS,asmundg/FreshRSS,FreshRSS/FreshRSS,plopoyop/FreshRSS,Alkarex/FreshRSS,plopoyop/FreshRSS,FreshRSS/FreshRSS,Dolomich/FreshRSS,Alkarex/FreshRSS,asmundg/FreshRSS,superboum/FreshRSS,Alkarex/FreshRSS,marienfressinaud/FreshRSS,FreshRSS/FreshRSS,superboum/FreshRSS,FreshRSS/FreshRSS,aledeg/FreshRSS,romibi/FreshRSS,aledeg/FreshRSS,marienfressinaud/FreshRSS,marienfressinaud/FreshRSS,Alkarex/FreshRSS