`vim.tbl_islist` is deprecated

[weskoerber]

Neovim version:

❯ nvim --version
NVIM v0.11.0-dev-13+g5f9e7edae
Build type: Release
LuaJIT 2.1.1713484068
Run "nvim -V1 -v" for more info

Upon starting neovim, I get this message:

vim.tbl_islist is deprecated, use vim.islist instead. :help deprecated                                                                                                                                                                    
Feature will be removed in Nvim 0.12                                                                                                                                                                                                      
Press ENTER or type command to continue

See:

• Related PR: https://github.com/neovim/neovim/issues/24572
• Breaking commit: https://github.com/neovim/neovim/commit/d9d890562e43493c999f8a6ff2b848959686f5b6