feat: Add countLeadingZeros new algorithm with Junit tests (#5703)

src/test/java/com/thealgorithms/bitmanipulation/CountLeadingZerosTest.java

@@ -0,0 +1,16 @@
+package com.thealgorithms.bitmanipulation;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class CountLeadingZerosTest {
+
+    @Test
+    public void testCountLeadingZeros() {
+        assertEquals(29, CountLeadingZeros.countLeadingZeros(5)); // 000...0101 has 29 leading zeros
+        assertEquals(32, CountLeadingZeros.countLeadingZeros(0)); // 000...0000 has 32 leading zeros
+        assertEquals(31, CountLeadingZeros.countLeadingZeros(1)); // 000...0001 has 31 leading zeros
+        assertEquals(0, CountLeadingZeros.countLeadingZeros(-1)); // No leading zeros in negative number (-1)
+    }
+}