### What changes were proposed in this pull request?
This PR aims to fix a correctness bug in the optimizer rule `EliminateSorts`. It also adds a new physical rule to remove redundant sorts that cannot be eliminated in the Optimizer rule after the bugfix.
### Why are the changes needed?
A global sort should not be eliminated even if its child is ordered since we don't know if its child ordering is global or local. For example, in the following scenario, the first sort shouldn't be removed because it has a stronger guarantee than the second sort even if the sort orders are the same for both sorts.
```
Sort(orders, global = True, ...)
Sort(orders, global = False, ...)
```
Since there is no straightforward way to identify whether a node's output ordering is local or global, we should not remove a global sort even if its child is already ordered.
### Does this PR introduce _any_ user-facing change?
Yes
### How was this patch tested?
Unit tests
Closes#30093 from allisonwang-db/fix-sort.
Authored-by: allisonwang-db <66282705+allisonwang-db@users.noreply.github.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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