How to install Undotree in NvChad?

I am learning to use NeoVim and have started with the NvChad base configuration and have setup a basic python LSP in it.

I recently saw a video where a person was using a plugin called UndoTree and wanted to install it in my setup, but I cannot seem to install it.

Here is my plugins.lua file which contains all the plugins for the lazy.nvim package manager

local plugins = {
  {
    "williamboman/mason.nvim",
    opts = {
      ensure_installed = {
        "black",
        "pyright",
        "mypy",
        "ruff",
      },
    },
  },
  {
    "neovim/nvim-lspconfig",
    config = function ()
      require "plugins.configs.lspconfig"
      require "custom.configs.lspconfig"
    end
  },
  -- Python Language Support
  {
    "jose-elias-alvarez/null-ls.nvim",
    ft = {"python"},
    opts = function ()
      return require "custom.configs.null-ls"
    end
  },
  -- Undo-Tree
    -- Added this plugin
    {
      "mbbill/undotree",
      lazy = false,
      config = function ()
        return require "custom.configs.undotree"
      end
    },
}

return plugins

This is the custom configuration file I have written for the UndoTree Plugin

local undotree = require('undotree')

undotree.setup({
  float_diff = true,  -- using float window previews diff, set this `true` will disable layout option
  layout = "left_bottom", -- "left_bottom", "left_left_bottom"
  ignore_filetype = { 'Undotree', 'UndotreeDiff', 'qf', 'TelescopePrompt', 'spectre_panel', 'tsplayground' },
  window = {
    winblend = 30,
  },
  keymaps = {
    ['j'] = "move_next",
    ['k'] = "move_prev",
    ['J'] = "move_change_next",
    ['K'] = "move_change_prev",
    ['<cr>'] = "action_enter",
    ['p'] = "enter_diffbuf",
    ['q'] = "quit",
  },
})

This is the error message I am getting after starting nvim

This is my :Lazy profile output