Timespan filter accept dates from behat tests improperly

[semteacher]

Timespan filter accept dates from behat tests improperly - as -1 day:

• Behat code

• effective values in the filter panel

(Note that same behavior had been spotted and reported (at least in chat) for wb_table plugin early)

[semteacher]

I have opened an issue under wb_table plugin so closing this one