Support for Pypy 3.7 in CI (#300)

pypy3.7 in CI

Author: chayim

.github/workflows/ci.yml

@@ -73,7 +73,7 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-latest ]
-        pyver: [ "3.6", "3.7", "3.8", "3.9", "3.10", "pypy-3.8" ]
+        pyver: [ "3.6", "3.7", "3.8", "3.9", "3.10", "pypy-3.8", "pypy-3.7" ]
         redisstack: [ "latest" ]
       fail-fast: false
     services: