Add editor::RevertSelectedHunks to revert git diff hunks in the editor (#9068)

https://github.com/zed-industries/zed/assets/2690773/653b5658-e3f3-4aee-9a9d-0f2153b4141b

Release Notes:

- Added `editor::RevertSelectedHunks` (`cmd-alt-z` by default) for
reverting git hunks from the editor

crates/project/src/project.rs

@@ -4427,7 +4427,6 @@ impl Project {
                                     project_transaction.0.extend(new.0);
                                 }
 
-                                // TODO kb here too:
                                 if let Some(command) = action.lsp_action.command {
                                     project.update(&mut cx, |this, _| {
                                         this.last_workspace_edits_by_language_server