Remove unnecessary waiting when handling save RPC requests

Add saving to the randomized integration test

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

crates/language/src/buffer.rs

@@ -1283,10 +1283,6 @@ impl Buffer {
         self.text.wait_for_edits(edit_ids)
     }
 
-    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = ()> {
-        self.text.wait_for_version(version)
-    }
-
     pub fn set_active_selections(
         &mut self,
         selections: Arc<[Selection<Anchor>]>,