fix: correct legacy require paths

Author: mbroadst

lib/operations/find.js

@@ -4,8 +4,8 @@ const OperationBase = require('./operation').OperationBase;
 const Aspect = require('./operation').Aspect;
 const defineAspects = require('./operation').defineAspects;
 const ReadPreference = require('../read_preference');
-const maxWireVersion = require('../core/utils').maxWireVersion;
-const MongoError = require('../core/error').MongoError;
+const maxWireVersion = require('../utils').maxWireVersion;
+const MongoError = require('../error').MongoError;
 
 class FindOperation extends OperationBase {
   constructor(collection, ns, command, options) {