Rewrite URLs of images in generator descriptions

to honor the static_url

scripts/boxesserver

@@ -290,8 +290,9 @@ class BServer:
         no_img_msg = _('There is no image yet. Please donate an image of your project on <a href=&quot;https://github.com/florianfesti/boxes/issues/140&quot;>GitHub</a>!')
 
         if box.description:
-            result.append(markdown.markdown(_(box.description),
-                                            extensions=["extra"]))
+            result.append(
+                markdown.markdown(_(box.description), extensions=["extra"])
+                .replace('src="static/', f'src="{static_url}/'))
 
         result.append(f'''<div>
 <img src="{static_url}/samples/{box.__class__.__name__}.jpg" width="100%" onerror="this.parentElement.innerHTML = '{no_img_msg}';">