remove unneded assignment

lib/contracts/deploy_manager.js

@@ -1,5 +1,9 @@
 let async = require('async');
 
+// TODO: remove contractsManager dependency
+// * use events
+// * in the engine use the instance instead
+
 class DeployManager {
   constructor(options) {
     const self = this;
@@ -10,7 +14,6 @@ class DeployManager {
     this.events = options.events;
     this.plugins = options.plugins;
     this.blockchain = options.blockchain;
-    this.chainConfig = (options.trackContracts !== false) ? this.config.chainTracker : false;
     this.contractsManager = options.contractsManager;
     this.gasLimit = false;
     this.fatalErrors = false;