force write command for scratch persistence file

[jakebasile]

When a persistence file and autoclose are both set, Vim will complain when trying to write to the persistence file:

Error detected while processing WinLeave Autocommands for "<buffer=3>"..function <SNR>100_close_window:
line    3:
E13: File exists (add ! to override)
Press ENTER or type command to continue

I added the magic ❗ and it appears to work for me.

(thanks for the plugin, by the way!)

[mtth]

Thanks @jakebasile!