Update PYTHON_LATEST in python-package.yml to 3.12

Author: wbarnha

.github/workflows/python-package.yml

@@ -15,7 +15,7 @@ env:
   FORCE_COLOR: "1"  # Make tools pretty.
   PIP_DISABLE_PIP_VERSION_CHECK: "1"
   PIP_NO_PYTHON_VERSION_WARNING: "1"
-  PYTHON_LATEST: "3.11"
+  PYTHON_LATEST: "3.12"
   KAFKA_LATEST: "2.6.0"
 
   # For re-actors/checkout-python-sdist