BREAKING CHANGE: deprecated WECHATY_SERVICE_DISCOVERY_ENDPOINT

[huan]

WECHATY_SERVICE_DISCOVERY_ENDPOINT is deprecated.

Before

export WECHATY_SERVICE_DISCOVERY_ENDPOINT=https://api.chatie.io

After

export WECHATY_PUPPET_SERVICE_AUTHORITY=api.chatie.io

Note: https is a MUST. http is not supported anymore.

Sunset schedule

The WECHATY_SERVICE_DISCOVERY_ENDPOINT will be removed after Dec 31, 2022

Related to: #155