test: Add comprehensive tests for JugglerSequence (#6947)

* test: Add comprehensive tests for JugglerSequence

- Added tests for input values 1, 2, 3, and 9
- Tests verify correct sequence output
- Improves code coverage for maths package

* fix: Format JugglerSequenceTest

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

@@ -0,0 +1,42 @@
+package com.thealgorithms.maths;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import org.junit.jupiter.api.Test;
+
+class JugglerSequenceTest {
+
+    @Test
+    void testJugglerSequenceWithThree() {
+        ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(outContent));
+        JugglerSequence.jugglerSequence(3);
+        assertEquals("3,5,11,36,6,2,1\n", outContent.toString());
+    }
+
+    @Test
+    void testJugglerSequenceWithTwo() {
+        ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(outContent));
+        JugglerSequence.jugglerSequence(2);
+        assertEquals("2,1\n", outContent.toString());
+    }
+
+    @Test
+    void testJugglerSequenceWithNine() {
+        ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(outContent));
+        JugglerSequence.jugglerSequence(9);
+        assertEquals("9,27,140,11,36,6,2,1\n", outContent.toString());
+    }
+
+    @Test
+    void testJugglerSequenceWithOne() {
+        ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(outContent));
+        JugglerSequence.jugglerSequence(1);
+        assertEquals("1\n", outContent.toString());
+    }
+}