cubicweb #2236352 uilib.print_timedelta thinks values between 0 and <1 day are negative [validation pending]

prioritynormal
typebug
done in3.14.6
load0.100
load left0.000
closed by#1385e05afe52 [uilib] don't print timedeltas between 0 and 23h as negative (closes #2236352)