Sending e-mail on register should handle the case where no e-mail server was configured

[italovalcy]

Hi,

Currently if you try to run the dashboard without configuring a e-mail server, eventually you may get errors like this:

2025-03-25 11:21:18,577 WARNING [apps] [routes.py:77] Failed login ipaddr=189.71.126.43 login=admin auth_provider=local
2025-03-25 11:22:49,313 ERROR [apps] [app.py:875] Exception on /register [POST]
Traceback (most recent call last):
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask/app.py", line 1511, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask/app.py", line 919, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask/app.py", line 917, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask/app.py", line 902, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/italo/dashboard/apps/authentication/routes.py", line 174, in register
    mail.send(msg)
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask_mail/__init__.py", line 539, in send
    with self.connect() as connection:
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask_mail/__init__.py", line 127, in __enter__
    self.host = self.configure_host()
                ^^^^^^^^^^^^^^^^^^^^^
  File "/home/italo/dashboard/venv/lib/python3.11/site-packages/flask_mail/__init__.py", line 149, in configure_host
    host.starttls()
  File "/usr/lib/python3.11/smtplib.py", line 769, in starttls
    self.ehlo_or_helo_if_needed()
  File "/usr/lib/python3.11/smtplib.py", line 611, in ehlo_or_helo_if_needed
    if not (200 <= self.ehlo()[0] <= 299):
                   ^^^^^^^^^^^
  File "/usr/lib/python3.11/smtplib.py", line 451, in ehlo
    self.putcmd(self.ehlo_msg, name or self.local_hostname)
  File "/usr/lib/python3.11/smtplib.py", line 378, in putcmd
    self.send(f'{s}{CRLF}')
  File "/usr/lib/python3.11/smtplib.py", line 365, in send
    raise SMTPServerDisconnected('please run connect() first')
smtplib.SMTPServerDisconnected: please run connect() first

We should have means to not fail when the e-mail server was not configured.