Atlassian's instruction on Configuring your firewall for UPM connectivity does not provide a list of IPs. The suggestion is to Customer use domain or find the IP by themselves:

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Since IP addresses for a given domain can change over time, Atlassian recommends that you configure your firewall policy by hostname rather than by numeric IP address. If you do need to configure rules by IP address, we suggest that you use a network analysis tool to investigate outgoing connections made by UPM. And keep in mind that you may need to update the rules on occasion, in this case.
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Other companies do keep an up-to-date list of IP ranges that we do use for our firewall configuration. For instance:
Github
Azure App Service

It would be helpful for System Admins if Atlassian also have a IP-ranges page for the Marketplace, with up-to-date IPs.