Containers not behaving the same as GH runners

[ngarafol]

I have weird issue with repo that I am working on.
If using GH runners, this workflow finishes ok https://github.com/moodlehq/moodleapp/blob/main/.github/workflows/testing.yml
but trying to run with act, it starts pulling ubuntu:full-latest docker image (I set large option), and it fails on https://github.com/moodlehq/moodleapp/blob/main/.github/workflows/testing.yml#L44 with unexpected operand error. If I replace == with -eq then error is integer expected or some other nonsense.
So, I am wondering what am I doing wrong, and is ubuntu:full-latest 1:1 copy of GH ubuntu-22.04 runner? Or, anyway, what should I do to make workflow work as with GH runners?

Thanks

[catthehacker]

is ubuntu:full-latest 1:1 copy of GH ubuntu-22.04 runner?

technically yes, but it can't behave exactly like GH runner since it's not a VM, it's not built as VM image and the runner might incorrectly parse workflow. Would be good to see if other image types work.