Add missing include.

sbenzaquen · shaod2 · commit d39063184a82 · 2025-05-14T10:08:18.000-04:00
PiperOrigin-RevId: 758201156
diff --git a/src/google/protobuf/descriptor.cc b/src/google/protobuf/descriptor.cc
@@ -26,6 +26,7 @@
 #include <limits>
 #include <memory>
 #include <new>  // IWYU pragma: keep
+#include <optional>
 #include <sstream>
 #include <string>
 #include <tuple>
