PYTHON-3174 Don't reinit client_context.client (#899)

Author: ShaneHarvey

test/test_raw_bson.py

@@ -20,7 +20,6 @@
 
 from test import client_context, unittest
 from test.test_client import IntegrationTest
-from test.utils import rs_or_single_client
 
 from bson import decode, encode
 from bson.binary import JAVA_LEGACY, Binary, UuidRepresentation
@@ -42,12 +41,6 @@ class TestRawBSONDocument(IntegrationTest):
     )
     document = RawBSONDocument(bson_string)
 
-    @classmethod
-    def setUpClass(cls):
-        super(TestRawBSONDocument, cls).setUpClass()
-        client_context.client = rs_or_single_client()
-        cls.client = client_context.client
-
     def tearDown(self):
         if client_context.connected:
             self.client.pymongo_test.test_raw.drop()