* add intelliJ idea's project configuration to gitignore
* upgrade mariadb from 10.5.3 to 10.5.9 for nextcloud
* add redis to nextcloud and upgrade from 19.0.0 to 21.0.1
* remove bad http port for nextcloud
* improve nextcloud end instructions
Co-authored-by: Simon Belbeoch <simon.belbeoch@octo.com>