message: Use a constant for MetaMask error code
diff: @@ -19,6 +19,8 @@ import { task } from 'ember-concurrency-decorators';
  import { taskFor } from 'ember-concurrency-ts';
  import Web3 from 'web3';
  +const ERR_METAMASK_UNKNOWN_NETWORK = 4902; // The requested chain has not been added by MetaMask
  +
  export default class Wallet extends Service {
  @service declare network: NetworkService;
  @@ -102,7 +104,7 @@ export default class Wallet extends Service {
  params: [{ chainId: chainIdHex }],
  });
  } catch (error) {
  - if (error.code === 4902) {
  + if (error.code === ERR_METAMASK_UNKNOWN_NETWORK) {
  // Network not added in Metamask. We prompt the user to add it.
  const networkName = convertChainIdToName(chainId);
  