[api-fuzzer] Fix use-after-free in api-fuzzer (#30707)
[api-fuzzer] Fix use-after-free in api-fuzzer (#30707)


jtattermusch/grpc,grpc/grpc,stanley-cheung/grpc,stanley-cheung/grpc,stanley-cheung/grpc,grpc/grpc,jtattermusch/grpc,grpc/grpc,jtattermusch/grpc,jtattermusch/grpc,jtattermusch/grpc,jtattermusch/grpc,grpc/grpc,stanley-cheung/grpc,grpc/grpc,stanley-cheung/grpc,jtattermusch/grpc,stanley-cheung/grpc,grpc/grpc,grpc/grpc,grpc/grpc,jtattermusch/grpc,jtattermusch/grpc,jtattermusch/grpc,stanley-cheung/grpc,grpc/grpc,grpc/grpc,stanley-cheung/grpc,stanley-cheung/grpc,jtattermusch/grpc,jtattermusch/grpc,stanley-cheung/grpc,stanley-cheung/grpc,grpc/grpc,stanley-cheung/grpc,grpc/grpc