Yes, follow Jira's documentation for integrating either an external SAML or OpenID Connect Provider for login. In Jira, you will configure Jira to request certain user information from Gluu, like email address. If the email address aligns with an existing user in Jira, Jira should make the association and not create a new user.
If you get it working, feel free to leave your configuration notes here for the community!
Thanks in advance,
Will