It appears that whatever website you are using to find these flights is not calculating the time zone difference correctly. However, it's wrong for an interesting reason.
Morocco is on the time zone UTC+1 (one hour ahead of UTC) for most of the year. The UK, meanwhile, observes UTC+1 during the summer (from the end of March to the end of October) but UTC+0 during the winter. Most websites would, I expect, take seasonal clock changes into account. If this was that needed to be taken into consideration, the flight time during the month of April would just be the differences in the clock times, and this is what your website showed you.
However, Morocco sets its clocks back to UTC+0 during Ramadan. (This makes the clock time of sunset earlier, which allows observant Muslims to break their fasts earlier.) By the Gregorian calendar, Ramadan lasts from April 2 to May 1 during 2022. This means that at the time of those flights, Rabat will still be one hour behind London; but it is entirely plausible to me that whoever coded this website did not take Ramadan into account, meaning that it calculates the flight times incorrectly. You could test out my hypothesis by using the same site to search for flight times after May 1, when Morocco will have returned to UTC+1.