update python runtime in system tests to 3.12

Author: parthea

noxfile.py

@@ -35,6 +35,8 @@
 DEFAULT_PYTHON_VERSION = "3.12"
 
 DEFAULT_MOCK_SERVER_TESTS_PYTHON_VERSION = "3.12"
+SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.12"]
+
 UNIT_TEST_PYTHON_VERSIONS: List[str] = [
     "3.7",
     "3.8",
@@ -60,7 +62,6 @@
 UNIT_TEST_EXTRAS: List[str] = []
 UNIT_TEST_EXTRAS_BY_PYTHON: Dict[str, List[str]] = {}
 
-SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.8"]
 SYSTEM_TEST_STANDARD_DEPENDENCIES: List[str] = [
     "mock",
     "pytest",