use node 18 for docker

docker/init.sh

@@ -8,6 +8,8 @@ else
     echo "Creating new bench..."
 fi
 
+export PATH="${NVM_DIR}/versions/node/v${NODE_VERSION_DEVELOP}/bin/:${PATH}"
+
 bench init --skip-redis-config-generation frappe-bench
 
 cd frappe-bench
@@ -36,4 +38,4 @@ bench --site lms.localhost clear-cache
 bench --site lms.localhost set-config mute_emails 1
 bench use lms.localhost
 
-bench start
+bench start