Make REST API return nothing when deleting user props.

clockwork_tools_test/test_mt_job_user_props.py

@@ -35,5 +35,6 @@ def test_cw_tools_delete_user_props(client):
     props = client.set_user_props(job_id, cluster_name, {"a new name": "a new prop"})
     assert props == {"name": "je suis une user prop 1", "a new name": "a new prop"}
 
-    props = client.delete_user_props(job_id, cluster_name, ["name"])
+    assert client.delete_user_props(job_id, cluster_name, ["name"]) == ""
+    props = client.get_user_props(job_id, cluster_name)
     assert props == {"a new name": "a new prop"}

clockwork_web/rest_routes/jobs.py

@@ -270,8 +270,7 @@ def route_user_props_delete():
 
     # Delete props, using current_user_id as mila email username.
     delete_user_props(job_id, cluster_name, keys, current_user_id)
-    props = get_user_props(job_id, cluster_name, current_user_id)
-    return jsonify(props)
+    return jsonify("")
 
 
 # Note that this whole `user_dict_update` thing needs to be rewritten

clockwork_web_test/test_rest_job_user_props.py

@@ -113,6 +113,13 @@ def test_jobs_user_props_delete(local_client, valid_rest_auth_headers_student00)
     )
     assert response.content_type == "application/json"
     assert response.status_code == 200
+    assert response.get_json() == ""
+
+    response = local_client.get(
+        f"/api/v1/clusters/jobs/user_props/get?cluster_name={cluster_name}&job_id={job_id}",
+        headers=valid_rest_auth_headers_student00,
+    )
+    assert response.status_code == 200
     props = response.get_json()
     assert props == {"other name": "other value"}