fix fmt

Author: mattsu2020

src/uu/uniq/src/uniq.rs

@@ -312,7 +312,7 @@ impl Uniq {
 
     // This function does not use `self`, so make it an associated function.
     // Also remove needless explicit lifetimes to satisfy clippy::needless-lifetimes.
-    fn build_count_prefix(count: usize,buf: &mut [u8; Self::COUNT_PREFIX_BUF_SIZE],) -> &[u8] {
+    fn build_count_prefix(count: usize, buf: &mut [u8; Self::COUNT_PREFIX_BUF_SIZE]) -> &[u8] {
         let mut digits_buf = [0u8; 20];
         let mut value = count;
         let mut idx = digits_buf.len();