Fix break in TestExpectations for virtual/pointerevent tests
crrev.com/2086283003 added a skip rule for virtual/pointerevent/...
This landed at the same time as crrev.com/2098883002 which removed the
entire virtual/pointerevent test suite. Somehow these both made it
through CQ, leaving TestExpecations in a bad sate.
Any future changes to TestExpectations now hit a lint error:
LayoutTests/TestExpectations:1201 Path does not exist. virtual/pointerevent/imported/wpt/pointerevents/pointerevent_properties_mouse-manual.html
This change removes the offending line (the line above it already
achieves the same thing for the non-virtual test, which is now the only