Handle Jenkins errors

[spbnick]

This adds detection of test errors (infrastructure failures) and makes sktm ignore Jenkins builds which have them, so that baseline is not degraded and patches are held in pendingpatches, both to be rechecked on subsequent runs.

[spbnick]

This is not tested yet, WIP.

[coveralls]

Pull Request Test Coverage Report for Build 376

• 1 of 18 (5.56%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 29.061%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
sktm/jenkins.py	0	8	0.0%
sktm/init.py	1	10	10.0%
<!--	Total:	1	18	5.56%	-->

Totals
Change from base Build 373:	0.3%
Covered Lines:	318
Relevant Lines:	922

---

💛 - Coveralls

[veruu]

While I didn't test it either and just checked the code, most of this is removal of unused code and cleanups and should be good to go :+1: the Jenkins part should be properly tested though

[spbnick]

I tested this mostly, still waiting for one job to finish, then we can merge this, and I'll deliver this to staging, along with the required pipeline changes.

[spbnick]

OK, tested with the new pipeline, success and infrastructure failure (cancelled Beaker jobs), baseline and patchwork commands worked fine. @veruu, do you think this is ready to go in?

[veruu]

I think so. And if there is something that breaks in a way we didn't expect we can fix it afterwards.

[spbnick]

Thank you, Veronika :)