✨(backend) manage uploaded file status and call to malware detection

In the attachment_upload method, the status in the file metadata to
processing and the malware_detection backend is called. We check in the
media_auth if the status is ready in order to accept the request.

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to
 
 - ✨ Add a custom callout block to the editor #892
 - 🚩(frontend) version MIT only #911
+- ✨(backend) integrate maleware_detection from django-lasuite #936
 
 ## Changed