Add Libretiny as platform

What's Changed

• Bump AsyncTCP-esphome version and add libretiny to platforms list by @jesserockz in #8

Full Changelog: v2.0.0...v2.1.0

v2.0.0

What's Changed

• Adapt for usage with LibreTiny platform by @kuba2k2 in #7

New Contributors

• @kuba2k2 made their first contribution in #7

Full Changelog: v1.1.1...v2.0.0