neovim: a deprecated warning of `vim.tbl_flatten()` is shown

[AsPulse]

- ⚠️ WARNING vim.tbl_flatten is deprecated. Feature will be removed in Nvim 0.13
  - ADVICE:
    - use vim.iter(…):flatten():totable() instead.
    - stack traceback:
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer/nvim.lua:96
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer.lua:588
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:387
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:135
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:395
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:362
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:197
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/handler/event.lua:85
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:175
    - stack traceback:
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer/nvim.lua:96
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer.lua:589
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:387
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:135
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:395
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:362
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:197
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/handler/event.lua:85
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:175
    - stack traceback:
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer/nvim.lua:96
        /Users/aspulse/.local/share/nvim/lazy/nvim-colorizer.lua/lua/colorizer.lua:617
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:387
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:135
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:395
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:362
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/loader.lua:197
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/handler/event.lua:85
        [C]:-1
        /Users/aspulse/.local/share/nvim/lazy/lazy.nvim/lua/lazy/core/util.lua:175