app.yml配置
DISCOURSE_SMTP_ADDRESS: smtp.qiye.aliyun.com
DISCOURSE_SMTP_PORT: 25
DISCOURSE_SMTP_USER_NAME: 邮箱
DISCOURSE_SMTP_PASSWORD: 密码
DISCOURSE_SMTP_OPEN_TIMEOUT: 15
DISCOURSE_SMTP_READ_TIMEOUT: 15
DISCOURSE_SMTP_AUTHENTICATION: login
DISCOURSE_SMTP_ENABLE_START_TLS: false