Cloud Spanner - March 17th, 2021 [Feature]

## Feature The Cloud Console query page has been updated with a revamped query editor, which now offers improved autocomplete, prevalidation of your query, formatting options, and the ability to run a selection from your query. This update also includes a new query plan visualizer. For a tour of these features and to learn more, see [Tuning a query using the query plan visualizer](https://cloud.google.com/spanner/docs/tune-query-with-visualizer).