Update vec.rs

Author: DrAsu33

library/alloctests/tests/vec.rs

@@ -2720,8 +2720,7 @@ fn vec_null_ptr_roundtrip() {
 
 // Regression test for Undefined Behavior (UB) caused by IntoIter::nth_back (#148682)
 // when dealing with high-aligned Zero-Sized Types (ZSTs).
-#[test] 
-#[cfg(miri)] 
+#[test]
 fn zst_vec_iter_nth_back_regression() {
     #[repr(align(8))]
     struct Thing;