Configure connection to mongodb for querying only

We have an external mongodb instance and we need to query data from it and bring it to Drupal 8 site.

On shell this is how we connect

mongo --host docker_mongo --ssl --sslCAFile=/etc/ssl/mongodb-cert.crt 

Could anyone suggest how to connect to a mongodb instance?
Adding the following at settings.php does not work and status report shows "No database aliases found in settings. Did you actually configure your settings ?"

$configureMongoDb = function (array $settings): array {
  $settings['mongodb'] = [
    'clients' => [
      // Client alias => connection constructor parameters.
      'mymongo' => [
        'uri' => 'mongodb://docker_mongo:27017',
        'uriOptions' => ['ssl=true&sslCAFile=/etc/ssl/mongodb-cert.crt'],
        'driverOptions' => [],
      ],
    ],
    'databases' => [
      // Database alias => [ client_alias, database_name ].
      'tutorial2' => ['mymongo', 'tutorial2'],
    ],
  ];

  return $settings;
};

Cross posted this query on drupal.stackexchange as well.