fix: fix version tag of abi3 wheels

Author: ntamas

setup.py

@@ -789,8 +789,8 @@ class bdist_wheel_abi3(bdist_wheel):
         def get_tag(self):
             python, abi, plat = super().get_tag()
             if python.startswith("cp"):
-                # on CPython, our wheels are abi3 and compatible back to 3.7
-                return "cp37", "abi3", plat
+                # on CPython, our wheels are abi3 and compatible back to 3.9
+                return "cp39", "abi3", plat
 
             return python, abi, plat
 else: