make import export visitor builder default export

Author: soryy708

src/exportMap/builder.js

@@ -16,7 +16,7 @@ import ExportMap from '.';
 import childContext from './childContext';
 import { isEsModuleInterop } from './typescript';
 import { RemotePath } from './remotePath';
-import { ImportExportVisitorBuilder } from './visitor';
+import ImportExportVisitorBuilder from './visitor';
 
 const log = debug('eslint-plugin-import:ExportMap');
 

src/exportMap/visitor.js

@@ -20,7 +20,7 @@ function makeSourceCode(text, ast) {
   }
 }
 
-export class ImportExportVisitorBuilder {
+export default class ImportExportVisitorBuilder {
   constructor(
     path,
     context,