This commit
3567a47258 fs: make ConfigString properly reverse suffixed file systems
made fs.ConfigString() return the full config of the backend. Because
mount was using this to make a volume name it started to make volume
names with illegal characters in which couldn't be mounted by macOS.
This fixes the problem by making a separate fs.ConfigStringFull() and
using that where appropriate and leaving the original
fs.ConfigString() function untouched.
Fixes#7063
See: https://forum.rclone.org/t/1-63-beta-fails-to-mount-on-macos-with-on-the-fly-crypt-remote/39090
Before this change we renamed file systems with overridden config with
{suffix}.
However this meant that ConfigString produced a value which wouldn't
re-create the file system.
This uses an internal hash to keep note of what config goes which
which {suffix} in order to remake the config properly.