feat: clock testing DX

[dgafka]

Why is this change proposed?

This is to improve DX when working with time (e.g. delayed messages).

        $messageChannel->send(
            MessageBuilder::withPayload('some')
                ->setHeader(MessageHeaders::DELIVERY_DELAY, 2000)
                ->build()
        );

        $ecotoneLite->waitTill(TimeSpan::withSeconds(1));

        $this->assertNull($messageChannel->receive());

        $ecotoneLite->waitTill(TimeSpan::withSeconds(3));

        $this->assertNotNull($messageChannel->receive());

Description of Changes

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