logs: log packageFile when failing to look up dependency

lib/manager/npm/package.js

@@ -57,7 +57,10 @@ async function getPackageUpdates(config) {
       message: `Failed to look up dependency ${config.depName}`,
     };
     results = [result];
-    logger.info({ dependency: config.depName }, result.message);
+    logger.info(
+      { dependency: config.depName, packageFile: config.packageFile },
+      result.message
+    );
   }
   for (const result of results) {
     result.repositoryUrl =