fix wrong placed `getBreadcrumb` module declaration

src/components/PageHeader/breadcrumb.d.ts

+import * as React from 'react';
+import { IPageHeaderProps } from './index'
+
+export default class BreadcrumbView extends React.Component<IPageHeaderProps, any> {}
+
+export function getBreadcrumb(breadcrumbNameMap: Object, url: string): Object;

src/components/PageHeader/index.d.ts

@@ -20,6 +20,4 @@ export interface IPageHeaderProps {
   hiddenBreadcrumb?:boolean;
 }
 
-export function getBreadcrumb(breadcrumbNameMap: Object, url: string): typeof Object;
-
 export default class PageHeader extends React.Component<IPageHeaderProps, any> {}

src/components/PageHeader/index.test.js

-import { getBreadcrumb } from './index';
+import { getBreadcrumb } from './breadcrumb';
 import { urlToList } from '../_utils/pathTools';
 
 const routerData = {