Drop PyPy 3.7 from GitHub Actions (ci.yml) (#4728)

* Remove `pypy-3.7` from ci.yml

* Update .github/workflows/ci.yml

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Co-authored-by: Henry Schreiner <HenrySchreinerIII@gmail.com>

Author: rwgk

.github/workflows/ci.yml

@@ -37,9 +37,9 @@ jobs:
         - '3.10'
         - '3.11'
         - '3.12'
-        - 'pypy-3.7'
         - 'pypy-3.8'
         - 'pypy-3.9'
+        - 'pypy-3.10'
 
         # Items in here will either be added to the build matrix (if not
         # present), or add new keys to an existing matrix element if all the