Bugfix: Max file upload

Although PHP allows max file upload of 256MB and we also advertise it on the UI, the real current max file upload is 60MB due to nginx client_max_body_size configuration. (nginx then throws 413 Request Entity Too Large)

Related:

• !96 (merged)
• https://gitlab.cern.ch/webservices/webframeworks-planning/-/issues/883
• Issue: INC3404041
• https://drupal-community.web.cern.ch/t/unable-to-upload-file/1394/19

Any reason for it to be this size? Change back to 256MB or properly document limit is 60MB.