Do NOT auto-pass first job

[jgfouca]

Description

Even though this is a small code change, this is a significant change to how CIME works. For reasons I don't understand, we had the first job in the workflow list skip the prereq check. I had no idea why we did this since it's easy to not provide a prereq if you don't want one. This design lead to surprises, like my case.build running at SUBMIT even though I had prereq set to False (since I never want to run it during SUBMIT).

This needs to be merged quickly so I can update E3SM's cime because a lot of stuff is broken there.

CESM folks may want to double-check their workflow XML to make sure this won't break you.

Checklist

• My code follows the style guidelines of this project (black formatting)
• I have performed a self-review of my own code
• My changes generate no new warnings
• I have added tests that exercise my feature/fix and existing tests continue to pass
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding additions and changes to the documentation

[jgfouca]

@billsacks , can you take a quick look at this? It could potentially impact CESM.

[billsacks]

@jgfouca - Do you have a sense of what, specifically, we should look for in our workflow xml file to make sure this won't break anything for us?

@mnlevy1981 and @fischer-ncar - also looping you two in, in the hopes that you might be more familiar with this workflow stuff than I am.

[jgfouca]

@billsacks , the CESM file looks OK to me. I don't see a workflow that won't run when it should.

[billsacks]

Thanks for looking & confirming, @jgfouca !