Remove some stale comments

src/highlight/highlight.rs

@@ -77,7 +77,7 @@ pub fn colorize(text: &wstr, colors: &[HighlightSpec], vars: &dyn Environment) -
         outp.writech(c);
     }
     outp.set_color(RgbColor::NORMAL, RgbColor::NORMAL);
-    outp.contents().to_owned() // TODO should move
+    outp.contents().to_owned()
 }
 
 /// Perform syntax highlighting for the shell commands in buff. The result is stored in the color

src/parse_execution.rs

@@ -1418,8 +1418,7 @@ fn expand_arguments_from_nodes(
                 ExpandResultCode::ok => {}
             }
 
-            // Now copy over any expanded arguments. Use std::move() to avoid extra allocations; this
-            // is called very frequently.
+            // Now copy over any expanded arguments.
             if let Some(additional) =
                 (out_arguments.len() + arg_expanded.len()).checked_sub(out_arguments.capacity())
             {