Docker: bump protobuf to 3.12.3
Docker: bump protobuf to 3.12.3

jinghaomiao/apollo,jinghaomiao/apollo,jinghaomiao/apollo,ApolloAuto/apollo,ycool/apollo,ycool/apollo,xiaoxq/apollo,xiaoxq/apollo,xiaoxq/apollo,jinghaomiao/apollo,ApolloAuto/apollo,ApolloAuto/apollo,xiaoxq/apollo,ApolloAuto/apollo,ycool/apollo,jinghaomiao/apollo,ApolloAuto/apollo,xiaoxq/apollo,ycool/apollo,xiaoxq/apollo,ycool/apollo,ycool/apollo,ApolloAuto/apollo,jinghaomiao/apollo