It's a Clubiona species. There are lots of them and it would need examination under the microscope to get it down to species. That said, looking at spur coming off its left palp, I think C. terrestris is a possibility.
Oops, ignore what I said about the protruding spur on the palp - it's on the wrong side for IDing it to species. Maybe it's just a clump of hair. But apart from that what I said was OK. It's a Clubiona, an adult male.