[2.3.0] Checkmk Werk 15725 created: Cleanup old Microcore config during update procedure

[//]: # (werk v2) # Cleanup old Microcore config during update procedure key | value ---------- | --- date | 2024-02-27T09:23:01+00:00 version | 2.3.0b1 class | fix edition | cre component | core level | 1 compatible | yes This change prevents a problem which might occur in case the `omd update` did not finish successfully. In this situation, the Microcore might be started with a configuration file from the previous version. This could lead to unexpected behavior. Instead of keeping the old configuration, the update procedure now deletes the file which makes the Microcore fail during startup with a more helpful error message.