ctp: mainnet nft bridge deployments (#3654)

* ctp: mainnet nft bridge deployments

* Create mighty-planets-pump.md
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

.changeset/mighty-planets-pump.md

+---
+"@eth-optimism/contracts-periphery": patch
+---
+
+mainnet nft bridge deployments

packages/contracts-periphery/src/nft-bridge-deploy-helpers.ts

@@ -24,6 +24,7 @@ export const isTargetL2Network = (network: string): boolean => {
 export const isTargetL1Network = (network: string): boolean => {
   switch (network) {
     case 'mainnet':
+    case 'ethereum':
     case 'goerli':
     case 'ops-l1':
     case 'kovan':
@@ -38,6 +39,7 @@ export const getProxyAdmin = (network: string): string => {
     case 'optimism':
       return l2MainnetMultisig
     case 'mainnet':
+    case 'ethereum':
       return l1MainnetMultisig
     case 'kovan':
     case 'optimism-kovan':