fix(analytics): anchor column resize handles to table headers (port of upstream PR 2274) #596

Port and adapt the upstream fix (Kpa-clawbot/CoreScope pull request number 2274; literal reference, not linked): column resize handles in analytics tables should be anchored to the table headers so they line up and stay usable when the table scrolls. Check our makeColumnsResizable usage and fix it with a browser test (desktop and mobile).