[lldb] Eliminate (_)Py_IsFinalizing (NFC) (#152226)

Looking at the implementation of `pylifecycle.c` in cpython, finalizing
and initialized are set at the same time. Therefore we can eliminate the
call to `Py_IsFinalizing` and only check `Py_IsInitialized`, which is
part of the stable API.

I converted the check to an assert and confirmed that during my test
suite runs, we never got into the if block. Because we check before
taking the lock, there is an opportunity for a race, but that exact same
race exists with the original code.

Author: JDevlieghere

lldb/source/Plugins/ScriptInterpreter/Python/PythonDataObjects.cpp

@@ -71,24 +71,11 @@ Expected<std::string> python::As<std::string>(Expected<PythonObject> &&obj) {
   return std::string(utf8.get());
 }
 
-static bool python_is_finalizing() {
-#if PY_VERSION_HEX >= 0x030d0000
-  return Py_IsFinalizing();
-#else
-  return _Py_IsFinalizing();
-#endif
-}
-
 void PythonObject::Reset() {
   if (m_py_obj && Py_IsInitialized()) {
-    if (python_is_finalizing()) {
-      // Leak m_py_obj rather than crashing the process.
-      // https://docs.python.org/3/c-api/init.html#c.PyGILState_Ensure
-    } else {
-      PyGILState_STATE state = PyGILState_Ensure();
-      Py_DECREF(m_py_obj);
-      PyGILState_Release(state);
-    }
+    PyGILState_STATE state = PyGILState_Ensure();
+    Py_DECREF(m_py_obj);
+    PyGILState_Release(state);
   }
   m_py_obj = nullptr;
 }