Fix clang-format: add newlines

Author: PauLopNun

src/main/java/com/thealgorithms/sorts/SleepSort.java

@@ -43,4 +43,4 @@ public static int[] sort(int[] array) {
 
         return result;
     }
-}
+}

src/test/java/com/thealgorithms/sorts/SleepSortTest.java

@@ -29,4 +29,4 @@ void testSingleElement() {
         int[] result = SleepSort.sort(input);
         assertArrayEquals(expected, result);
     }
-}
+}