We have our forum registered on the Google Search Console, I have just checked that we don't have any security issue on our site. I have tried to request a password reset from a test user account, but I didn't get any "suspicious link" warning on the password reset mail on GMail. What might be triggering this warning is the fact that we're using a personal email address as the sender's mail instead of one from our domain. I'm in touch with our host provider for a mail account which we could use for official communications.
Sorry for the inconvenience.
Varti