E482: Can't open tmp file for writing: no such file or directory, solution proposed.

- [x] I have read through https://github.com/junegunn/fzf.vim/blob/master/README.md
- [x] I have read through https://github.com/junegunn/fzf/blob/master/README-VIM.md
- [x] I have read through the manual page of fzf (`man fzf`)
- [x] I have searched through the existing issues

Everytime I put my laptop to sleep, then wake up, FZF wont work cause its expecting TMP files which arent there anymore. If one closes Neovim, and restart Neovim, then it works (sometimes this involves closing many working buffers).

This is a sample error message:
```
Error detected while processing function fzf#vim#buffers[3]..99_fzf[18]..fzf#run:
line 27:
E482: Can't open file C:\Users\Michael\AppData\Local\Temp\nvimwTDIgy\7 for writing: no such file or directory
```
@junegunn , in [this closed issue](https://github.com/junegunn/fzf.vim/issues/260) you mentioned :
> I don't think there's something we can do about it.

But I propose when FZF tries to access a tmp file, if the tmp file, or dir the tmp file is in does not exist, then to create a new one instead of causing an error.