Fix broken split tests.
Fix broken split tests.

I added a prefix to each test to isolate working files.

dennis/coreutils,efuquen/coreutils,filmor/coreutils,uutils/coreutils,beni55/coreutils,hexsel/coreutils,kwantam/coreutils,beni55/coreutils,sshling/coreutils,uutils/coreutils,tempbottle/coreutils,Heather/coreutils,bundai223/coreutils,kball/coreutils,keunwoo/coreutils,Shir0kamii/coreutils,Shir0kamii/coreutils,dennis/coreutils,retep998/coreutils,wimh/coreutils,kevgeniy/coreutils,keunwoo/coreutils,silvio/rust-coreutils,dbrgn/coreutils,kevgeniy/coreutils,sshling/coreutils,steveklabnik/coreutils,hexsel/coreutils,ebfe/coreutils,Heather/coreutils,steveklabnik/coreutils,Arcterus/coreutils,wimh/coreutils,kball/coreutils,bundai223/coreutils,Arcterus/coreutils,retep998/coreutils,dbrgn/coreutils,dbrgn/coreutils,ebfe/coreutils,filmor/coreutils,uutils/coreutils,kwantam/coreutils,efuquen/coreutils,tempbottle/coreutils,Shtong/coreutils,mauricio/coreutils,jbcrail/coreutils,samfoo/coreutils,Shtong/coreutils,samfoo/coreutils,silvio/rust-coreutils,mauricio/coreutils,jbcrail/coreutils