Security hardening fixed

[Aymuos22]

Updated OpenML/docker/config/php.ini to harden the PHP runtime: turned off expose_php so responses no longer include the PHP signature, and raised max_input_time to 3600 seconds to keep multi‑GB multipart uploads from failing mid‑stream.

Adjusted OpenML/docker/config/api.conf so the document root uses Options -Indexes ..., preventing Apache from serving directory listings for the API.