extract printer mail to settings file

src/utils/richtext.py

@@ -167,7 +167,7 @@ class SemesterDocument:
         port = config.mail.port
         sender_email = config.mail.sender
         password = config.mail.password
-        receiver = "mobileprint@ph-freiburg.de"
+        receiver = config.mail.printer_mail
         message = MIMEMultipart()
         message["From"] = sender_email
         message["To"] = receiver