ci: Only use one artifact instruction for logs.
Having the different types of logs in artifacts instruction makes it quicker
to navigate between them. Either that didn't use to be possible, or I just did
it wrong. I saw that / how it works in a patch by Justin Pryzby.
Also remove a few unnecessary uses of **, suggested by Justin Pryzby.
Discussion: https://postgr.es/m/
20220203195718.smqo5xg4ygp5qktq@alap3.anarazel.de