Drag-and-drop improvements for projects and issue pins (#29875)
1. Add "grabbing" cursor while dragging items:
2. Make project board only drag via their header, not via their whole
body.
3. Fix some cursor problems in projects
4. Move shared options into `createSortable`.
(cherry picked from commit 7fda109aba6cd077343edef086b2f2ff60124f78)
47c61f909c