nixos/nextcloud: preserve OC_PASS env variable in the occ wrapper

The OC_PASS environment variable can be used to create a user with
`occ user:add --password-from-env`. It is currently not possible to
use the `nextcloud-occ` to "non-interactively" create a user since
this variable is ignored by sudo.

nixos/modules/services/web-apps/nextcloud.nix

@@ -34,7 +34,7 @@ let
     cd ${cfg.package}
     sudo=exec
     if [[ "$USER" != nextcloud ]]; then
-      sudo='exec /run/wrappers/bin/sudo -u nextcloud --preserve-env=NEXTCLOUD_CONFIG_DIR'
+      sudo='exec /run/wrappers/bin/sudo -u nextcloud --preserve-env=NEXTCLOUD_CONFIG_DIR --preserve-env=OC_PASS'
     fi
     export NEXTCLOUD_CONFIG_DIR="${cfg.home}/config"
     $sudo \