Support nvim-treesitter `main` branch

[ofseed]

nvim-treesitter is gradually refactoring, it has a branch that does not provide the nvim-treesitter lua module. Now nvim-treesitter-textobject supports the main branch of nvim-treesitter, so I hope this plugin can support it one day since it will be the only valid branch.

Reference to https://github.com/nvim-treesitter/nvim-treesitter/tree/main https://github.com/nvim-treesitter/nvim-treesitter-textobjects/tree/main

[ghostbuster91]

Thanks for the heads up. Yes, I will definitely do it one day. In the meantime, of course, PRs are welcome :)