:wrench: Brevo's email api changed again

backend/lib/services/user.js

 
 // Configuration for Brevo
 const Brevo = require('@getbrevo/brevo')
-const defaultClient = Brevo.ApiClient.instance
-const apiKey = defaultClient.authentications['api-key']
-apiKey.apiKey = process.env.BREVO_KEY
 const apiInstance = new Brevo.TransactionalEmailsApi()
+const apiKey = apiInstance.authentications.apiKey
+apiKey.apiKey = process.env.BREVO_KEY
 const sendSmtpEmail = new Brevo.SendSmtpEmail()
 
 // TODO: Consider implementing, nice use of SecurePassword,