fix: typo in error message

Author: AntoineGS

lua/copilot/config/should_attach.lua

@@ -6,7 +6,7 @@ local should_attach = {
   ---@type ShouldAttachFunc
   default = function(_, _)
     if not vim.bo.buflisted then
-      logger.debug("not attaching, bugger is not 'buflisted'")
+      logger.debug("not attaching, buffer is not 'buflisted'")
       return false
     end