treesitter: ignore parser for dockerfile

see [issue 51](camdencheek/tree-sitter-dockerfile#51)

Author: maxisacson

lua/setup/treesitter.lua

@@ -1,5 +1,6 @@
 require 'nvim-treesitter.configs'.setup {
     ensure_installed = { "lua", "vim", "vimdoc", "c", "cpp", "python", "bash" },
+    ignore_install =  { "dockerfile" },
     auto_install = true,
     highlight = {
         enable = true,