Fix clippy lints

src/ipc/client.rs

@@ -220,7 +220,7 @@ pub fn handle_msg(mut msg: Msg, json: bool) -> anyhow::Result<()> {
 
             let print = |surface: &niri_ipc::LayerSurface| {
                 println!("    Surface:");
-                println!("      Namespace: \"{}\"", &surface.namespace);
+                println!("      Namespace: \"{}\"", surface.namespace);
 
                 let interactivity = match surface.keyboard_interactivity {
                     niri_ipc::LayerSurfaceKeyboardInteractivity::None => "none",

src/protocols/ext_workspace.rs

@@ -200,7 +200,7 @@ fn refresh_workspace_group(protocol_state: &mut ExtWorkspaceManagerState, output
     // Send workspace_enter for all existing workspaces on this output.
     for group in &data.instances {
         let manager: &ExtWorkspaceManagerV1 = group.data().unwrap();
-        for (_, ws) in protocol_state.workspaces.iter() {
+        for ws in protocol_state.workspaces.values() {
             if ws.output.as_ref() != Some(output) {
                 continue;
             }

src/protocols/output_management.rs

@@ -250,7 +250,7 @@ impl OutputManagementManagerState {
                 notify_new_head(self, output, conf);
             }
         }
-        for (old, _) in self.current_state.iter() {
+        for old in self.current_state.keys() {
             if !new_state.contains_key(old) {
                 changed = true;
                 notify_removed_head(&mut self.clients, old);