Remove pypy 3.9

Author: rmk135

.github/workflows/tests-and-linters.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        python-version: [3.7, pypy3.9]
+        python-version: [3.7]
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4