add conditional semi colon

docker-mods/nginx-proxy-manager/root/etc/cont-init.d/98-themepark

@@ -4,8 +4,7 @@ echo '--------------------------------------'
 echo '| Nginx Proxy Manager theme.park Mod |' 
 echo '--------------------------------------'
 
-if [ -d "/app/frontend" ]
+if [[ -d "/app/frontend" ]]; then
-then
     APP_FILEPATH='/app/frontend/' # jc21/nginx-proxy-manager
 else
     APP_FILEPATH='/opt/nginx-proxy-manager/frontend/' # jlesage/nginx-proxy-manager