Add optional suffix to dependency

[linyihai]

Addressed #2397

Add optional suffix to dependency.

[GuillaumeGomez]

Looks good to me. Please add a test.

[linyihai]

Looks good to me. Please add a test.

The test case was appended to the last commit.

[linyihai]

The test stuck in the GUI_test for a long time.

[GuillaumeGomez]

Restarted the GUI test job.

[syphar]

Thank you for this improvement!

I did a manual test, and taking the fs-err example it looks like this:

I feel like the structure could be improved by having a visual distinction between the dependency groups and the "optional" test, but IMO it's fine for now.

[linyihai]

I feel like the structure could be improved by having a visual distinction between the dependency groups and the "optional" test, but IMO it's fine for now.

Thank you for review this. I am not very good at visual design, if there is a clear design scheme, I am willing to try to improve it.