fix the indexOf instead by simulating what solc does

lib/modules/deployment/contract_deployer.js

@@ -230,9 +230,6 @@ class ContractDeployer {
             if (linkReference.length > 40) {
               return next(new Error(__("{{linkReference}} is too long, try reducing the path of the contract ({{filename}}) and/or its name {{contractName}}", {linkReference: linkReference, filename: filename, contractName: contractObj.className})));
             }
-            if (contractCode.indexOf(linkReference) < 0) {
-              continue;
-            }
             let toReplace = linkReference + "_".repeat(40 - linkReference.length);
             if (deployedAddress === undefined) {
               let libraryName = contractObj.className;