Simplify test_de
Simplify test_de

infinityb/serde,JohnHeitmann/serde,eefriedman/serde,Ticki/serde,skade/serde,Byron/serde,jmesmon/serde,tempbottle/serde,serde-rs/serde,erickt/serde,oli-obk/rust-serde,sidred10/serde,thorbenk/serde,pcwalton/serde,Hoverbear/serde,csmulhern/serde,3Hren/serde