php – How to add a data-attribute to a input field in magento2

I have the below code in LayoutProcessorPlugin.php file in my module

<?php
 $customAttributeCode = 'custom_field';
 $customField = (
 'component' => 'Magento_Ui/js/form/element/abstract',
 'config' => (
    // customScope is used to group elements within a single form (e.g. they can be validated separately)
    'customScope' => 'shippingAddress.custom_attributes',
    'customEntry' => null,
    'template' => 'ui/form/field',
    'elementTmpl' => 'ui/form/element/input',
    'tooltip' => (
        'description' => 'this is what the field is for',
    ),
),
'dataScope' => 'shippingAddress.custom_attributes' . '.' . $customAttributeCode,
'label' => 'Custom Attribute',
'provider' => 'checkoutProvider',
'sortOrder' => 0,
'validation' => (
   'required-entry' => true
),
'options' => (),
'filterBy' => null,
'customEntry' => null,
'visible' => true,
'value' => '' // value field is used to set a default value of the attribute
);

 $jsLayout('components')('checkout')('children')('steps')('children')('shipping-step')('children')('shippingAddress')('children')('shipping-address-fieldset')('children')($customAttributeCode) = $customField;

Above code will render a custom input field to checkout page.

I need to add a data attribute like data-label to the rendered HTML field.
What should I modify to the LayoutProcessorPlugin.php to do so?