Update drupal Docker tag to v10.2.6

This MR contains the following updates:

Package	Type	Update	Change
drupal		patch	10.2.5-fpm -> 10.2.6-fpm
drupal	ironbank-docker	patch	10.2.5-fpm -> 10.2.6-fpm
drupal	stage	patch	10.2.5-fpm -> 10.2.6-fpm

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