Breadcrumbs fix (#628)

* breadcrumbs fix

* fix curly brackets on import

* Create moody-carrots-know.md

Author: emilybrick

.changeset/moody-carrots-know.md

@@ -0,0 +1,5 @@
+---
+"@primer/gatsby-theme-doctocat": patch
+---
+
+- Add withPrefix to breadcrumbs

theme/src/components/layout.js

@@ -15,6 +15,7 @@ import StorybookLink from './storybook-link'
 import FigmaLink from './figma-link'
 import TableOfContents from './table-of-contents'
 import navItems from '../nav.yml'
+import {withPrefix} from 'gatsby'
 
 const getPageAncestry = (url, object) => {
   const result = []
@@ -112,7 +113,7 @@ function Layout({children, pageContext, path}) {
               {breadcrumbData.length > 1 ? (
                 <Breadcrumbs sx={{mb: 4}}>
                   {breadcrumbData.map(item => (
-                    <Breadcrumbs.Item key={item.url} href={item.url} selected={path === item.url}>
+                    <Breadcrumbs.Item key={item.url} href={withPrefix(item.url)} selected={path === item.url}>
                       {item.title}
                     </Breadcrumbs.Item>
                   ))}