Checkmk Werk 10290: Temperature check GUI: fix rendering crash when rules are set

ID: 10290 Title: Temperature check GUI: fix rendering crash when rules are set Component: WATO Level: 2 Class: Bug fix Version: 1.7.0i1 10290 FIX Temperature check: fix rendering crash and reporting mismatch When a check sends a device-specific levels in a specific format the temperature rendering function of the service display could crash due to a type mismatch. This werk fixes this crash. Upon fixing this crash another bug was discovered and fixed. In the case of user specified levels being set and the service being in mode "Use your own levels if present, otherwise the device's", the device levels were not ignored and thus the wrong levels were checked. This is now fixed as well. No additional action is needed.