Add Pronic Number (#2867)

* Add Pronic Number

* Update directory

* Add unit tests for Pronic Number implementation

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
Co-authored-by: Andrii Siriak <siryaka@gmail.com>

src/test/java/com/thealgorithms/maths/PronicNumberTest.java

@@ -0,0 +1,34 @@
+package com.thealgorithms.maths;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class PronicNumberTest {
+
+    @Test
+    void testForPronicNumber() {
+
+        //given
+        int number = 30;
+
+        //when
+        boolean result = PronicNumber.isPronic(number);
+        
+        //then
+        assertTrue(result);
+    }
+
+    @Test
+    void testForNonPronicNumber() {
+        
+        //given
+        int number = 21;
+
+        //when
+        boolean result = PronicNumber.isPronic(number);
+        
+        //then
+        assertFalse(result);
+    }
+}