wsltty portable installer silently fails to install when selected folder has spaces

[Raven-Singularity]

When trying to install to a custom folder, I discovered if the folder has spaces in it, the installer will silently fail to copy any files and pops up the message saying "Mintty for WSL Portable installation finished".

For example this folder fails:

C:\Portable_Apps\General\Terminal_Emulators\MinTTY-WSL v3.7.6

While this folder works fine:

C:\Portable_Apps\General\Terminal_Emulators\MinTTY-WSL_v3.7.6

It would be good if the installer was updated to quote folder names in a way that doesn't break when there are spaces in them.

[mintty]

Released 3.7.6.2.