Fix: Go solution for Iterative DFS in Invert Binary Tree is using recursive code

[prithesh07]

Problem Reference

• Problem: 0226-invert-binary-tree.go
• Language: Go
• Section: 3. Iterative DFS

Issue Description

The code snippet under Iterative DFS for Go is currently displaying the recursive implementation instead of using an explicit stack.

Current Code (Incorrect):

func invertTree(root *TreeNode) *TreeNode {
    if root == nil {
        return nil
    }

    root.Left, root.Right = root.Right, root.Left

    invertTree(root.Left)
    invertTree(root.Right)

    return root
}