chirpstack login

login接口对接：

携带用户名和密码返回jwt

api/internal/login

{
  "email": "336@qq.com",
  "password": "123456"
}
返回
{ "jwt": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJhdWQiOiJhcyIsImV4cCI6MTY4MDcwNTMwMywiaWQiOjEyLCJpc3MiOiJhcyIsIm5iZiI6MTY4MDYxODkwMywic3ViIjoidXNlciIsInVzZXJuYW1lIjoiMzM2QHFxLmNvbSJ9.5xuQzVY2ieMT4-fJqLsAtdY4bUNpdqgq0F3_O7g4Myg" }