Update data_source_name in documentation

Signed-off-by: Neaj Morshad <[email protected]>

documentation/sql_exporter.yml

@@ -35,7 +35,7 @@ target:
   name: mssql_database
   # Data source name always has a URI schema that matches the driver name. In some cases (e.g. MySQL)
   # the schema gets dropped or replaced to match the driver expected DSN format.
-  data_source_name: 'sqlserver://prom_user:[email protected]:1433'
+  data_source_name: 'sqlserver://prom_user:[email protected]:1433/master'
 
   # Collectors (referenced by name) to execute on the target.
   collectors: [mssql_standard]