Make SliceBox::DESCRIPTION null-terminated

Author: kngwyu

src/slice_box.rs

@@ -38,7 +38,7 @@ unsafe impl<T> type_object::PyTypeInfo for SliceBox<T> {
     type AsRefTarget = PyCell<Self>;
     const NAME: &'static str = "SliceBox";
     const MODULE: Option<&'static str> = Some("_rust_numpy");
-    const DESCRIPTION: &'static str = "Memory store for PyArray using rust's Box<[T]>.";
+    const DESCRIPTION: &'static str = "Memory store for PyArray using rust's Box<[T]> \0";
     const FLAGS: usize = 0;
 
     #[inline]