High PostgreSQL load after upgrade from 11.1.3 to 12.1.1

### What happened? After upgrading Grafana from version 11.1.3 to 12.1.1, I started experiencing severe performance issues when using PostgreSQL as the backend database. My setup has a large number of organizations, and I am using both the Zabbix API datasource and the PostgreSQL datasource. Once the upgrade was completed, the PostgreSQL server load started spiking to very high values and then dropping again, constantly oscillating. This behavior was not present in version 11.1.3. The issue caused significant performance degradation, and the only way I could stabilize the environment was by performing a rollback to 11.1.3. ### What did you expect to happen? Whitout problem about performance ### Did this work before? Whitout problem about performance ### How do we reproduce it? Install Grafana 11.1.3 with PostgreSQL as backend (stable, no issues). Upgrade to Grafana 12.1.1. Use multiple organizations with Zabbix API datasource and PostgreSQL datasource. Monitor PostgreSQL server load → observe constant spikes and oscillations. ### Is the bug inside a dashboard panel? _No response_ ### Environment (with versions)? Grafana version: 11.1.3 (stable) → 12.1.1 (problematic) Database: PostgreSQL 15 OS: Oracle Linux 8.10 Plugins: Zabbix datasource PostgreSQL datasource ### Grafana platform? None ### Datasource(s)? _No response_