rpcsrv: fix TestSubClientWaitWithMissedEvent

Increase waiting interval for subscriptions awaiting up to 2 seconds.
Failing is caused by slow subscriptions.

Close #2958

Signed-off-by: Ekaterina Pavlova <ekt@morphbits.io>

pkg/services/rpcsrv/client_test.go

@@ -2064,7 +2064,7 @@ func testSubClientWaitWithMissedEvent(t *testing.T, local bool) {
 		rpcSrv.subsLock.Lock()
 		defer rpcSrv.subsLock.Unlock()
 		return len(rpcSrv.subscribers) == 1
-	}, time.Second, 100*time.Millisecond)
+	}, 2*time.Second, 100*time.Millisecond)
 
 	rpcSrv.subsLock.Lock()
 	// Suppress normal event delivery.