fix: remove unneeded code

src/sorting/selection_sort.rs

@@ -1,22 +1,13 @@
 pub fn selection_sort<T: Ord>(arr: &mut [T]) {
     let len = arr.len();
-
-    if len < 2 {
-        return;
-    }
-
     for left in 0..(len - 1) {
         let mut smallest = left;
-
         for right in (left + 1)..len {
             if arr[right] < arr[smallest] {
                 smallest = right;
             }
         }
-
-        if left != smallest {
-            arr.swap(left, smallest);
-        }
+        arr.swap(smallest, left);
     }
 }