[iomgr] remove spammy log message accidentally added in #36195 (#37017)

Closes #37017

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/37017 from markdroth:iomgr_endpoint_remove_unnecessary_log 1c3d04cbb2
PiperOrigin-RevId: 645512854

src/core/lib/iomgr/tcp_posix.cc

@@ -806,7 +806,6 @@ static void tcp_ref(grpc_tcp* tcp) { tcp->refcount.Ref(); }
 #endif
 
 static void tcp_destroy(grpc_endpoint* ep) {
-  gpr_log(GPR_INFO, "IOMGR endpoint shutdown");
   grpc_tcp* tcp = reinterpret_cast<grpc_tcp*>(ep);
   ZerocopyDisableAndWaitForRemaining(tcp);
   grpc_fd_shutdown(tcp->em_fd, absl::UnavailableError("endpoint shutdown"));