Hello @cthivierge , thank you for reaching out. There won't be any problem if you use the already provided self-signed certificate. Regarding the renewal of the certificates, you would have to renew that manually, but, before the cert expires, there would be a notification email that you would receive updating you about the date for the cert expiration.
You can check the following article for configuring the notification email and also steps for renewing the certificate here: https://learn.microsoft.com/en-us/azure/active-directory/manage-apps/manage-certificates-for-federated-single-sign-on#add-email-notification-addresses-for-certificate-expiration
The following article is worth checking out as it speaks about managing the certs SSO in Azure AD: https://learn.microsoft.com/en-us/azure/active-directory/manage-apps/manage-certificates-for-federated-single-sign-on
Hope this helps.
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