[Build] Fix json error (#33051)

To fix this error

```
test/core/security/grpc_authorization_engine_test.cc:88:32: error: unknown type name 'Json'; did you mean 'experimental::Json'?
  ParseAuditLoggerConfig(const Json&) override {
                               ^~~~
                               experimental::Json
```

test/core/security/grpc_authorization_engine_test.cc

@@ -24,6 +24,7 @@
 #include <grpc/grpc_audit_logging.h>
 #include <grpc/grpc_security_constants.h>
 
+#include "src/core/lib/json/json.h"
 #include "src/core/lib/security/authorization/audit_logging.h"
 #include "test/core/util/evaluate_args_test_util.h"