Make some dependency changes, support Python 3.10 and 3.11 (#5611)

Co-authored-by: jack1142 <6032823+jack1142@users.noreply.github.com>

redbot/pytest/rpc.py

@@ -7,8 +7,10 @@ __all__ = ["rpc", "rpcmixin", "cog", "existing_func", "existing_multi_func"]
 
 
 @pytest.fixture()
-def rpc():
-    return RPC()
+async def rpc():
+    rpc = RPC()
+    await rpc._pre_login()
+    return rpc
 
 
 @pytest.fixture()