Replace the manual unsafe C-string construction with the safe c"arrow_array_stream" macro, eliminating the need for the clippy suppression and unsafety

Author: kosiew

src/dataframe.rs

@@ -58,9 +58,7 @@ use crate::{
     expr::{sort_expr::PySortExpr, PyExpr},
 };
 
-#[allow(clippy::manual_c_str_literals)]
-static ARROW_STREAM_NAME: &CStr =
-    unsafe { CStr::from_bytes_with_nul_unchecked(b"arrow_array_stream\0") };
+static ARROW_STREAM_NAME: &CStr = c"arrow_array_stream";
 
 // https://github.com/apache/datafusion-python/pull/1016#discussion_r1983239116
 // - we have not decided on the table_provider approach yet