Update enum-aggregate-generic.rs

Fix double blank lines in enum-aggregate-generic.rs

Author: CaiWeiran

tests/codegen/enum/enum-aggregate-generic.rs

@@ -3,7 +3,6 @@
 //@ only-64bit
 //@ ignore-riscv64
 
-
 #![crate_type = "lib"]
 
 use std::cmp::Ordering;