feat(SqlLab): Change Save Dataset Button to Split Save Query Button IV (#20852)

* Moving entire split save btn PR

* Addressed review comments

* Remove arbitrary div from ErrorBoundary in Chart

* Added accidentally removed comment

* Fix act errors in SaveQuery tests

* Fix SaveDatasetActionButton test

* SaveDatasetModal test almost working

* SaveDatasetModal tests all passing

* Clean SaveDatasetModal test

* Fix create chart button and SaveDatasetModal text in SQL Lab

* Fix untitled dataset name on SaveDatasetModal in explore

* Fix styling on split save button

superset-frontend/src/utils/datasourceUtils.js

@@ -18,7 +18,7 @@
  */
 export const getDatasourceAsSaveableDataset = source => ({
   columns: source.columns,
-  name: source?.datasource_name || 'Untitled',
+  name: source?.datasource_name || source?.name || 'Untitled',
   dbId: source.database.id,
   sql: source?.sql || '',
   schema: source?.schema,