Which version of ruby is required

Summary

Inconsistency between manual (https://docs.gitlab.com/ce/install/installation.html#2-ruby) and what

su -l git -c "cd /usr/local/www/gitlab-ce && rake gitlab:check RAILS_ENV=production"
...
Ruby version >= 2.3.5 ? ... yes (2.4.6)
...

reports. Regarding the manual ruby version 2.5.x is required, regarding gitlab:check ruby >= 2.3.5 is required.

Could you please clarify what is correct?

Results of GitLab environment info

Gitlab version is 11.9.7.

Possible fixes

Update manual and/or gitlab:check.