Simplify by removing many std::move of shared_ptr to tracks...

... Don't need them, as we did with std::unique_ptr

src/LabelDialog.cpp

@@ -392,7 +392,7 @@ bool LabelDialog::TransferDataFromWindow()
       // Create the NEW track and add to track list
       auto newTrack = mFactory.NewLabelTrack();
       newTrack->SetName(name);
-      mTracks->Add(std::move(newTrack));
+      mTracks->Add( newTrack );
       tndx++;
    }