Add Python 3.11 to the test matrix (#948)

Author: elprans

.github/workflows/tests.yml

@@ -17,7 +17,7 @@ jobs:
     # job.
     strategy:
       matrix:
-        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11.0-rc.2"]
         os: [ubuntu-latest, macos-latest, windows-latest]
         loop: [asyncio, uvloop]
         exclude: