Fixed the GriddedSurface.get_surface_boundaries
Fixed the GriddedSurface.get_surface_boundaries


Former-commit-id: f04d1002c10d9231786a87659be728dd21da8d0b [formerly f04d1002c10d9231786a87659be728dd21da8d0b [formerly 0a2d994fc98055e5be021163c580f326700d5b3e]]
Former-commit-id: 850d62f72e3e4bc49a3944a7de1567c2848299c5
Former-commit-id: bdf1e39fc2a8cc8484c8daeeb177d2ed7ce35f65
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine