Interfere's with other plugin's UI

Vanilla [CMake-Tools](https://github.com/Civitasv/cmake-tools.nvim):
![image](https://github.com/hood/popui.nvim/assets/37873142/a6897647-05c7-4b7a-8a5b-a4e9345224c9)


Modified by global `vim.ui`:
![image](https://github.com/hood/popui.nvim/assets/37873142/baa1d51a-fa42-41b1-8f38-76eb391570bf)
