1.16.0版本在protobuf版本4.24环境编译失败

[Searion]

Describe the bug
/src/json2pb/json_to_pb.cpp 555
/src/json2pb/pb_to_json.cpp 136
error: 'const class google::protobuf::Descriptor::ExtensionRange' has no member named 'start'; did you mean 'start_'?

To Reproduce

Expected behavior
编译通过

Versions
OS: Ubuntu 22.04
Compiler: gcc 13
brpc: 1.16.0
protobuf: 4.24

Additional context/screenshots

查了一下GOOGLE_PROTOBUF_VERSION < 4025000这个版本判断应该设的太高了，4.x以上应该都要用start_number()了

[yanglimingcn]

#3210