tiny gossip comm test change

Sometimes the consumer in the test doesn't get enough CPU time so sending
too much messages may fail since the sending is now buffered.

Change-Id: Ib20c00a9deb384ad3ef5f6d11794e5dc71d99791
Signed-off-by: Yacov Manevich <yacovm@il.ibm.com>

gossip/comm/comm_test.go

@@ -256,7 +256,7 @@ func TestParallelSend(t *testing.T) {
 	defer comm1.Stop()
 	defer comm2.Stop()
 
-	messages2Send := 20
+	messages2Send := defRecvBuffSize
 
 	wg := sync.WaitGroup{}
 	go func() {
@@ -359,7 +359,7 @@ func TestAccept(t *testing.T) {
 	go readIntoSlice(&evenResults, evenNONCES)
 	go readIntoSlice(&oddResults, oddNONCES)
 
-	for i := 0; i < 100; i++ {
+	for i := 0; i < defRecvBuffSize; i++ {
 		comm2.Send(createGossipMsg(), &RemotePeer{Endpoint: "localhost:7611", PKIID: []byte("localhost:7611")})
 	}