cargo fmt

I hear git has an `absorb` extension, but I don't have it. :(

arrow-buffer/src/util/bit_mask.rs

@@ -131,7 +131,7 @@ unsafe fn set_upto_64bits(
 #[inline]
 unsafe fn read_bytes_to_u64(data: &[u8], offset: usize, count: usize) -> u64 {
     debug_assert!(count <= 8);
-    let mut tmp : u64 = 0;
+    let mut tmp: u64 = 0;
     let src = data.as_ptr().add(offset);
     unsafe {
         std::ptr::copy_nonoverlapping(src, &mut tmp as *mut _ as *mut u8, count);