[libc++][NFC] fix exception_guard include guard name (#131370)

Author: huixie90

libcxx/include/__utility/exception_guard.h

@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef _LIBCPP___UTILITY_TRANSACTION_H
-#define _LIBCPP___UTILITY_TRANSACTION_H
+#ifndef _LIBCPP___UTILITY_EXCEPTION_GUARD_H
+#define _LIBCPP___UTILITY_EXCEPTION_GUARD_H
 
 #include <__assert>
 #include <__config>
@@ -140,4 +140,4 @@ _LIBCPP_END_NAMESPACE_STD
 
 _LIBCPP_POP_MACROS
 
-#endif // _LIBCPP___UTILITY_TRANSACTION_H
+#endif // _LIBCPP___UTILITY_EXCEPTION_GUARD_H