#3 MQTT/stat/heatingOffTime shows wrong value after some time

after uptime 4:24 it shows i.E.: 02:133:4294960124

no issue found yet, further analysis required

partially fixed with commit 7b8b691e10 . Now heatingOnTime and heatingOffTime is published in seconds, for H:m:s format there is now a 2nd topic. No error in getTimeStringFromSeconds() found but when there is a bug then in this (unnecessary comfort) function.