message: fix bug where `workspace = true` would not show up after `update_toml`
diff: @@ -539,7 +539,9 @@ impl Dependency {
  }
  }
  Some(Source::Workspace(_)) => {
  + table.insert("workspace", toml_edit::value(true));
  table.set_dotted(true);
  + key.fmt();
  for key in [
  "version",
  "registry",
  