PresharedKey is now only set in the server and client config if the key
is set and not null (or empty).
I added this feature because I was importing old config files from
clients that did not have a preshared key set. Clients can be created
without preshared keys when editing db/client/ files manually. If the
field is not set, wireguard-ui creates invalid configs by producing:
PresharedKey =
This patch remvoes this behavior and just skips the preshared key if not
set.
Co-authored-by: Khanh Ngo <k@ndk.name>
