FIX: Ensure software-update banner is only shown after 24 hours (PR #12634)

isTesting is a function, so if(isTesting) was only checking for the presence of the function. We need to actually evaluate it. Followup to 68a032a7348dbf264f4d2db5f5dae5d0ecfdb7bd



I believe it’s the second time I get caught by this. It’s actually often annoying to remember, because ofc the test will be right :sweat_smile: