Email server configuration (#246)

Co-authored-by: riggraz <riccardo.graziosi97@gmail.com>

app/mailers/application_mailer.rb

@@ -1,5 +1,15 @@
 class ApplicationMailer < ActionMailer::Base
-  default from: "notifications@astuto.io"
   layout 'mailer'
   helper :application
+
+  after_action :set_mail_from_for_multitenancy
+
+  private
+  
+    def set_mail_from_for_multitenancy
+      if Rails.application.multi_tenancy?
+        from = "#{Current.tenant_or_raise!.site_name} <#{ENV.fetch('EMAIL_MAIL_FROM', 'notifications@astuto.io')}>"
+        mail.from = from
+      end
+    end
 end