Ensure `absl/base/casts.h` usage of `typeid` is well-formed

PiperOrigin-RevId: 857291008
Change-Id: Ieb46a451a0b1468c5105aa7c93c7c57e1fc57119
diff --git a/absl/base/casts.h b/absl/base/casts.h
index 2e13b4a..38243d8 100644
--- a/absl/base/casts.h
+++ b/absl/base/casts.h
@@ -27,6 +27,7 @@
 #include <cstring>
 #include <memory>
 #include <type_traits>
+#include <typeinfo>
 #include <utility>
 
 #ifdef __has_include