feat(live_grep): rg_glob with custom command (#1927)

Author: ibhagwan

lua/fzf-lua/providers/grep.lua

@@ -46,7 +46,7 @@ local get_grep_cmd = function(opts, search_query, no_esc)
   -- be reworked into a table of arguments
   opts._cmd = command
 
-  if opts.rg_glob and not command:match("^rg") then
+  if opts.rg_glob and not opts.rg_glob_fn not command:match("^rg") then
     if not tonumber(opts.rg_glob) and not opts.silent then
       -- Do not display the error message if using the defaults (rg_glob=1)
       utils.warn("'--glob|iglob' flags require 'rg', ignoring 'rg_glob' option.")