[File] lua file detected as javascript

[Avid Seeker]

$ wget 'https://raw.githubusercontent.com/ibhagwan/fzf-lua/refs/heads/main/lua/fzf-lua/defaults.lua'
&& file defaults.lua

Expected text/plain but file reads that as: `defaults.lua: JavaScript source,
Unicode text, UTF-8 text`

I reached the following as a minimal reproducible example. If the last
function is deleted, the file is detected as text/plain.

```
local path = require "fzf-lua.path"
local utils = require "fzf-lua.utils"
local actions = require "fzf-lua.actions"
local previewers = require "fzf-lua.previewer"

local M = {}

function M._default_previewer_fn()
  local winopts = M.globals.winopts
  if type(winopts) == "function" then
    winopts = winopts() or {}
    winopts.preview = type(winopts.preview) == "table" and winopts.preview or {}
    winopts.preview.default = winopts.preview.default or M.defaults.winopts.preview.default
  end
  local previewer = M.globals.default_previewer or winopts.preview.default
  -- the setup function cannot have a custom previewer as deepcopy
  -- fails with stack overflow while trying to copy the custom class
  -- the workaround is to define the previewer as a function instead
  -- https://github.com/ibhagwan/fzf-lua/issues/677
  return type(previewer) == "function" and previewer() or previewer
end

function M._preview_pager_fn()
  return vim.fn.executable("delta") == 1 and ("delta --width=$COLUMNS --%s"):format(vim.o.bg) or
      nil
end

function M._man_cmd_fn(bat_pager)
  local cmd = utils.is_darwin() and "man -P cat"
      or vim.fn.executable("mandb") == 1 and "man"
      or "man -c"
  local bat_cmd = bat_pager and (function()
    for _, bin in ipairs({ "batcat", "bat" }) do
      if vim.fn.executable(bin) == 1 then
        return string.format("%s --color=always -p -l man", bin)
      end
    end
  end)()
  local pager = bat_cmd or "col -bx"
  return string.format("%s %%s 2>/dev/null | %s", cmd, pager)
end
```