Rename ExpandAllHunkDiffs to ExpandAllDiffHunks (#25369)

This is more consistent with the nomenclature in the rest of Zed.

Release Notes:

- Renamed the `editor::ExpandAllHunkDiffs` action to
`editor::ExpandAllDiffHunks`
4118f42d61Cole Miller committed on 2/22/2025, 12:06:03 AM· committed by GitHubparentec56755
5 files changedLine totals unavailable