do not parse mappings with lua implementations (#233)

Co-authored-by: burnettk <[email protected]>

autoload/which_key/mappings.vim

@@ -45,6 +45,12 @@ function! which_key#mappings#parse(key, dict, visual) " {{{
  endif
 
  for line in lines
+ " filter out lines like: n <Space>ca *@<Lua 129: /opt/homebrew/Cellar/neovim/0.9.0/share/nvim/runtime/lua/vim/lsp/buf.lua:758>
+ " we're not going to get anything useful to display from the rhs of these anyway
+ if line =~? '<Lua '
+ continue
+ endif
+
  let mapd = maparg(split(line[3:])[0], line[0], 0, 1)
  if empty(mapd) || mapd.lhs =~? '<Plug>.*' || mapd.lhs =~? '<SNR>.*'
  continue