Fix typos and simplification

app/corpora/files/json_routes.py

@@ -1,4 +1,4 @@
-from flask import current_app, jsonify
+from flask import current_app
 from threading import Thread
 from app import db
 from app.decorators import content_negotiation
@@ -27,6 +27,4 @@ def delete_corpus_file(corpus_id, corpus_file_id):
         'message': f'Corpus File "{corpus_file.title}" marked for deletion',
         'category': 'corpus'
     }
-    response = jsonify(response_data)
-    response.status_code = 202
-    return response
+    return response_data, 202