Describe the bug

When formatting a SortPreservingMergeExec node with a limit, there's no space or line break between the expression and the limit.
For example:

To Reproduce

1. Create table with WITH ORDER clause, backed by multiple files.
2. Run a query with both a limit and ORDER BY clause that matches the table's order, prefixed with EXPLAIN FORMAT TREE.

Expected behavior

Like other fields and nodes, have a separate line for the limit.

Additional context

No response