PHP ObjectSerializer.sanitizeForSerialization wrong Parameters

[srikrishnudu]

We used the swagger-codegen-cli-3.0.26.jar to generate the PHP Classes.
The class ObjectSerializer.php is generated with the static function
public static function sanitizeForSerialization($data, $format = null) {}

Inside the same static function we see the line.
$values[$data::attributeMap()[$property]] = self::sanitizeForSerialization($value, $swaggerType, $formats[$property]);

The parameter swaggerType is wrongly assigned to format. We used the following schema definition.

"birth_date": { "type": "string", "format": "date" },

Can you please check this?