feat: added close to supported methods for cursors

Author: Michael Kryukov

mongomock_motor/__init__.py

@@ -91,6 +91,12 @@ def wrapper(self, *args, **kwargs):
         'where',
     ],
 )
+@with_async_methods(
+    '__cursor',
+    [
+        'close',
+    ],
+)
 class AsyncCursor:
     def __init__(self, cursor):
         self.__cursor = cursor
@@ -178,6 +184,12 @@ async def to_list(self, *args, **kwargs):
         'update_one',
     ],
 )
+@with_async_methods(
+    '__cursor',
+    [
+        'close',
+    ],
+)
 class AsyncMongoMockCollection:
     def __init__(self, database, collection):
         self.database = database