The Pulpcore version in Satellite 6.10 needs to be upgraded to 3.14 to get the latest tasking system among other numerous fixes.
I'll be making a downstream MR to Katello to get these changes in.
I didn't realize that 6.10 was still being built with upstream gems, so no MR should be needed.
Moving this bug to POST for triage into Satellite since the upstream issue https://projects.theforeman.org/issues/32933 has been resolved.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: Satellite 6.10 Release), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2021:4702