At my previous job, we had a "Devops" team. We even outsourced some ops to a third party in the worst possible way (I'm talking "oh you want to set up an alert for something related to your service? Send us an email and we'll look into it" and so on). All the pre-devops pain magnified by an order of magnitude. Sometimes devs would do their own ops (I know, big shock!), and they would call it "shadow devops". Nearly fell off my chair when I first heard it. Kinda glad I'm not with them anymore.
Yeah, and it's useful to just check everything so you don't forget to add some essential system package for e.g. SSL, especially when working with Alpine.
Unit tests? No matter where you run them, and normally this is done by CI in a prebuilt container image, so you don't have to wait for "docker building". Acceptance tests must be run in an environment as close to production as possible, but that's definitely not a programmer's job.