Follow-up to 1912b834b1

Fixed a typo in SupportSpotsGenerator, where thin fills were pulled
    from an incorrect region.

src/libslic3r/SupportSpotsGenerator.cpp

@@ -617,7 +617,6 @@ std::tuple<ObjectPart, float> build_object_part_from_slice(const LayerSlice &sli
                 }
             }
         }
-        const LayerRegion *thin_fill_region = layer->get_region(island.fill_region_id);
         for (const auto &thin_fill_idx : island.thin_fills) {
             add_extrusions_to_object(perimeter_region->thin_fills().entities[thin_fill_idx], perimeter_region);
         }