<?php

/**
 * Implements hook_views_data_alter().
 */
function my_module_views_data_alter(array &$data) {
  $data['node__profile_birthday']['birthday'] = [
    'title' => t('Filter by birthday'),
    'group' => t('Content'),
    'help'  => t('Filter profiles by birthday.'),
    'filter' => [
      'id'    => 'birthday',
      'field' => 'profile_birthday_value'
    ],
  ];
}

<?php

namespace Drupalmy_modulePluginviewsfilter;

use DrupalviewsPluginviewsfilterNumericFilter;


/**
 * Basic filter handler for Birthdays.
 *
 * @ViewsFilter("birthday")
 */
class Birthday extends NumericFilter {
  /**
   * Override the original Views opBetween behavior.
   */
  protected function opBetween($field) {
    // The birthdate is between -3 days and +7 days from the current date
    $expression = "DAYOFYEAR($field) BETWEEN ((DAYOFYEAR(CURRENT_DATE())) - 3) AND ((DAYOFYEAR(CURRENT_DATE())) + 7)";

    $this->query->addWhereExpression($this->options['group'], $expression);

  }

}