OK, I believe now I understand better your use case. You have a Focal system where you installed pacemaker which pulled in pacemaker-resource-agents as a runtime dependency which also pulled in resource-agents (containing pgsql agent). So when you upgrade to Jammy, apt will try to keep what you have installed which is pacemaker, it will still pull in pacemaker-resource-agents but now resource-agents-base is pulled in instead of resource-agents. This is intentional, since the idea is to let users use agents curated by Ubuntu Server by default. If they want to use non-curated agents they need to explicitly install them via resource-agents-extra.
The pgsql is in resource-agents-extra in Jammy and it is a suggested dependency (via Suggests:) of pacemaker-resource-agents. Therefore, it is not installed by default, you would need to explicit tell apt to do so.
I believe the only solution for the upgrade here is manually installing resource-agents in Focal, then after the upgrade you will have the resource-agents transitional package installing both resource-agents-base and resource-agents-extra. Relying on pacemaker dependencies chain would not work in this case as you have experienced that. Or installing resource-agents-extra manually after the upgrade (which I believe is what you did).
OK, I believe now I understand better your use case. You have a Focal system where you installed pacemaker which pulled in pacemaker- resource- agents as a runtime dependency which also pulled in resource-agents (containing pgsql agent). So when you upgrade to Jammy, apt will try to keep what you have installed which is pacemaker, it will still pull in pacemaker- resource- agents but now resource- agents- base is pulled in instead of resource-agents. This is intentional, since the idea is to let users use agents curated by Ubuntu Server by default. If they want to use non-curated agents they need to explicitly install them via resource- agents- extra.
The pgsql is in resource- agents- extra in Jammy and it is a suggested dependency (via Suggests:) of pacemaker- resource- agents. Therefore, it is not installed by default, you would need to explicit tell apt to do so.
I believe the only solution for the upgrade here is manually installing resource-agents in Focal, then after the upgrade you will have the resource-agents transitional package installing both resource- agents- base and resource- agents- extra. Relying on pacemaker dependencies chain would not work in this case as you have experienced that. Or installing resource- agents- extra manually after the upgrade (which I believe is what you did).