Fixing flapper

Since acks are now processed in different go-routine, the tests
that use Ack() cannot expect the number of ack messages to be
exact immediately. So in this test use AckSync() to ensure that
the ack is processed. Alternatively, the pending count should
be checked with a checkFor().

Signed-off-by: Ivan Kozlovic <ivan@synadia.com>

server/const.go

@@ -41,7 +41,7 @@ var (
 
 const (
 	// VERSION is the current version for the server.
-	VERSION = "2.7.5-beta.2"
+	VERSION = "2.7.5-beta.3"
 
 	// PROTO is the currently supported protocol.
 	// 0 was the original

server/jetstream_test.go

@@ -16054,7 +16054,7 @@ func TestJetStreamConsumerAckSampling(t *testing.T) {
 
 	mp := 0
 	for _, m := range fetchMsgs(t, asub, total, time.Second) {
-		err = m.Ack()
+		err = m.AckSync()
 		require_NoError(t, err)
 		mp++
 	}
@@ -16068,7 +16068,7 @@ func TestJetStreamConsumerAckSampling(t *testing.T) {
 	require_NoError(t, err)
 
 	// Should be ~250
-	if nmsgs < 100 || nmsgs > 400 {
+	if nmsgs < 200 || nmsgs > 300 {
 		t.Fatalf("Expected about 250, got %d", nmsgs)
 	}
 }