fix: missing autocommand group for deletion

Author: jo-pouradier

lua/float-preview.lua

@@ -333,6 +333,7 @@ function FloatPreview:attach(bufnr)
   table.insert(
     au,
     vim.api.nvim_create_autocmd("BufDelete", {
+      group = "float_preview_au",
       callback = function()
         vim.api.nvim_del_user_command "TogglePreviewFile"
       end,