fix: hoist use above global allocators

Signed-off-by: Martijn Swaagman <martijn@swaagman.online>

src/allocator.rs

@@ -12,12 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::mem::MaybeUninit;
+
 #[cfg(feature = "wee-alloc")]
 #[global_allocator]
 static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
 
-use std::mem::MaybeUninit;
-
 #[cfg_attr(
     all(target_arch = "wasm32", target_os = "unknown"),
     export_name = "malloc"