requirements: Upgrade moto to latest version.

Fixes #5454

requirements/moto.txt

@@ -4,6 +4,9 @@ Werkzeug==0.12.2
 click==6.7
 httpretty==0.8.10
 itsdangerous==0.24
-moto==0.4.31
+moto==1.0.1
 xmltodict==0.11.0
 python-dateutil==2.6.0
+cookies==2.2.1
+PyYAML==3.12
+botocore==1.5.72

zerver/tests/test_upload.py

@@ -44,7 +44,7 @@ import base64
 from datetime import timedelta
 from django.utils.timezone import now as timezone_now
 
-from moto import mock_s3
+from moto import mock_s3_deprecated
 
 from typing import Any, Callable, TypeVar, Text
 
@@ -972,7 +972,7 @@ FuncT = TypeVar('FuncT', bound=Callable[..., None])
 
 def use_s3_backend(method):
     # type: (FuncT) -> FuncT
-    @mock_s3
+    @mock_s3_deprecated
     @override_settings(LOCAL_UPLOADS_DIR=None)
     def new_method(*args, **kwargs):
         # type: (*Any, **Any) -> Any