editor: Fix multicursor indent edge case where few lines would indent incorrectly (#30461)

This should have been part of [editor: Fix inconsistent relative indent
when using tab with multi
cursors](https://github.com/zed-industries/zed/pull/29519)

Before / After:


https://github.com/user-attachments/assets/b7ab0eef-2764-44dc-b51f-b96dccd5ecb3

Release Notes:

- N/A

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Co-authored-by: Ben Kunkle <ben.kunkle@gmail.com>
172a475515Smit Barmase committed on 5/10/2025, 1:13:15 PM· committed by GitHubparent471e02d
2 files changedLine totals unavailable