Fix TestCreateServiceSecretFileMode, TestCreateServiceConfigFileMode

These tests wer failing frequently:

    === RUN   TestCreateServiceSecretFileMode
        create_test.go:291: assertion failed: 2 (int) != 1 (int)
    --- FAIL: TestCreateServiceSecretFileMode (7.88s)
    === RUN   TestCreateServiceConfigFileMode
        create_test.go:355: assertion failed: 2 (int) != 1 (int)
    --- FAIL: TestCreateServiceConfigFileMode (7.87s)

Which likely is because the client.TaskList() was only filtering by
service, and not by desired state of the tasks. In case the service
failed to start (several retries needed), this would also return
the failed tasks in the result.

This patch changes the tests to use the GetRunningTasks() utility,
which only returns tasks that are expected to be running.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

integration/service/create_test.go

@@ -282,13 +282,8 @@ func TestCreateServiceSecretFileMode(t *testing.T) {
 
 	poll.WaitOn(t, swarm.RunningTasksCount(client, serviceID, instances), swarm.ServicePoll)
 
-	filter := filters.NewArgs()
-	filter.Add("service", serviceID)
-	tasks, err := client.TaskList(ctx, types.TaskListOptions{
-		Filters: filter,
-	})
-	assert.NilError(t, err)
-	assert.Check(t, is.Equal(len(tasks), 1))
+	tasks := swarm.GetRunningTasks(t, client, serviceID)
+	assert.Check(t, is.Equal(len(tasks), instances))
 
 	body, err := client.ContainerLogs(ctx, tasks[0].Status.ContainerStatus.ContainerID, types.ContainerLogsOptions{
 		ShowStdout: true,
@@ -346,13 +341,8 @@ func TestCreateServiceConfigFileMode(t *testing.T) {
 
 	poll.WaitOn(t, swarm.RunningTasksCount(client, serviceID, instances))
 
-	filter := filters.NewArgs()
-	filter.Add("service", serviceID)
-	tasks, err := client.TaskList(ctx, types.TaskListOptions{
-		Filters: filter,
-	})
-	assert.NilError(t, err)
-	assert.Check(t, is.Equal(len(tasks), 1))
+	tasks := swarm.GetRunningTasks(t, client, serviceID)
+	assert.Check(t, is.Equal(len(tasks), instances))
 
 	body, err := client.ContainerLogs(ctx, tasks[0].Status.ContainerStatus.ContainerID, types.ContainerLogsOptions{
 		ShowStdout: true,