Add example with two endpoints

[oleksiikutuzov]

Going through different matter device types and trying to make them work with HomeKit, I created another example of using a plugin unit device (socket or switch in HomeKit terms). It is pretty similar to a Light example here, but has two endpoints and controls two outputs. I thought it would be helpful to add it.

[Yacubane]

Tested one endpoint with CHIPTool (I could not find option to test second endpoint). It works! Second endpoint is visible in CHIPTool (it's possible to query for it). From code perspective it should work.

Thank you for your contribution!

I'm aware that this testing process is questionable, but I don't want to stop this PR as it may be useful for other. Since Matter is not very mature yet (yeah, my Nest hub is still waiting till Google decides to push update on it, because I have no control over it) and there are some discrepancies between platforms I think that review process does not have to be so strict.

[oleksiikutuzov]

Yeah, that was also my point to test which device types are actually supported right now (I couldn't make temperature or occupancy sensors work wird default configuration, even though they should be supported according to tables) and how they are represented in different apps.