fix: use canonical path in windows (#977)

lua/nvim-tree.lua

@@ -118,7 +118,7 @@ function M.find_file(with_open)
 
   local bufname = vim.fn.bufname()
   local bufnr = api.nvim_get_current_buf()
-  local filepath = vim.fn.fnamemodify(bufname, ':p')
+  local filepath = utils.canonical_path(vim.fn.fnamemodify(bufname, ':p'))
   if not is_file_readable(filepath) then
     return
   end