fix asyncio tests

Author: BYK

tests/integrations/aiohttp/test_aiohttp.py

@@ -55,7 +55,7 @@ async def hello(request):
     assert request["url"] == "http://{host}/".format(host=host)
     assert request["headers"] == {
         "Accept": "*/*",
-        "Accept-Encoding": "gzip, deflate",
+        "Accept-Encoding": "gzip, deflate, br",
         "Host": host,
         "User-Agent": request["headers"]["User-Agent"],
         "baggage": mock.ANY,