fix: motion with segment policy must have Segment dist

sbroad-core/src/ir.rs

sbroad-core/src/ir/distribution.rs

sbroad-core/src/ir/operator.rs

...ore/src/ir/transformation/redistribution/tests/segment.rs

...r/transformation/redistribution/multiple_sub_queries.yaml

...ormation/redistribution/segment_motion_for_sub_query.yaml