Example
https://localhost:44333/api/ExchangeRate/update { "exchange_rate": 3.5925, "currency_input" : 2, "currency_output" : 1 }
https://localhost:44333/api/ExchangeRate/calculate { "amount_input": 10000, "currency_input" : 2, "currency_output" : 1 }
https://localhost:44333/api/login {"username": "USERAPP"}