ops: Update prod scripts for testnet4

production/mempool-start-all

@@ -4,7 +4,7 @@ source "$NVM_DIR/nvm.sh"
 nvm use v20.12.0
 
 # start all mempool backends that exist
-for site in mainnet mainnet-lightning testnet testnet-lightning signet signet-lightning liquid liquidtestnet;do
+for site in mainnet mainnet-lightning testnet testnet-lightning testnet4 signet signet-lightning liquid liquidtestnet;do
     cd "${HOME}/${site}/backend/" && \
     echo "starting mempool backend: ${site}" && \
     screen -dmS "${site}" sh -c 'while true;do npm run start-production;sleep 1;done'