Remove the old migrate_tools_sync state entry

Closes #3497145

migrate_tools.install

@@ -53,3 +53,10 @@ function migrate_tools_update_10000(): void {
     \Drupal::database()->schema()->createTable($tableName, $schemaDefinition);
   }
 }
+
+/**
+ * Remove the old migrate_tools_sync state entry.
+ */
+function migrate_tools_update_10001(): void {
+  \Drupal::state()->delete('migrate_tools_sync');
+}