Set clock on Xiaomi LYWSD02

**Describe the problem you have/What new integration you would like**

Synchronize clock on Xiaomi BLE Thermometer LYWSD02 Model via SNTP

**Please describe your use case for this integration and alternatives you've tried:**

Before you can use this device you must setup it using smartphone and official app to setup clock and timezone. But if this FR will be implemented this step can be skipped. After adding device to ESPhome it can be synced via SNTP and get timezone automatically (from HomeAssistant or configured in YAML via options).

**Additional context**

Setting timezone can be skipped or forced to another value by supplying option in YAML config. My LYWSD02 clock drift to +1 minute in 1 month, so periodical SNTP syncing would be good too. Syncing frequency can be set in YAML option too. I found working code to set clock and timezone for this device at Mikhail Baranov's github: https://github.com/h4/lywsd02