fix: remove incorrect nvim-treesitter.configs main module reference

[fyzanshaik]

Summary

• Remove incorrect main = 'nvim-treesitter.configs' reference
• The actual module file is config.lua (singular), not configs.lua
• This fixes "module 'nvim-treesitter.configs' not found" error on startup
• lazy.nvim will correctly load plugin using default module path

Issue

Fixes #1732 and resolves widespread issue where users get:

Failed to run `config` for nvim-treesitter
module 'nvim-treesitter.configs' not found

Root Cause

nvim-treesitter plugin renamed its main module from configs.lua to config.lua, but kickstart.nvim still references the old module name.

Testing

• Verified plugin loads correctly without main specification
• Confirmed nvim-treesitter functionality works as expected
• No breaking changes to existing configuration options

[fyzanshaik]

Closing as duplicate of #1748 which addresses the same nvim-treesitter configs.lua -> config.lua module rename issue. Thanks to @philwhln for the original fix!