chore: better empty tree handling

Author: ridge-kimani

Diff for: Data-Structures/Tree/test/BinarySearchTree.test.js

@@ -59,7 +59,8 @@ describe('Binary Search Tree', () => {
   })
 
   test('should handle empty tree gracefully', () => {
-    expect(tree.search(22)).toBeNull()
-    tree.removeValue(22) // Should not throw
+    const newTree = new Tree()
+    newTree.removeValue(22) // Should not throw
+    expect(newTree.search(22)).toBeNull()
   })
 })