Make RPCTimeout for udp_send_recv_dgram to be 500 milliseconds.

The test will sometimes fail on Bind calls using the old RPCTimeout.

PiperOrigin-RevId: 356646668

test/packetimpact/tests/udp_send_recv_dgram_test.go

@@ -32,6 +32,7 @@ import (
 
 func init() {
 	testbench.Initialize(flag.CommandLine)
+	testbench.RPCTimeout = 500 * time.Millisecond
 }
 
 type udpConn interface {