`addToClockTime noTimeDiff` is not the identity function

It looks like `addToClockTime` is badly broken:
~~~~
*System.Time> let c = TOD ((19078*24+2)*3600+1357) 0
*System.Time> c
Sun Mar 27 04:22:37 CEST 2022
*System.Time> addToClockTime noTimeDiff c
Sun Mar 27 05:22:37 CEST 2022
*System.Time> addToClockTime noTimeDiff $ addToClockTime noTimeDiff c
Sun Mar 27 05:22:37 CEST 2022
~~~~