Automatic merge from submit-queue (batch tested with PRs 39695, 37054, 39627, 39546, 39615)

Always --pull in docker build to ensure recent base images

**What this PR does / why we need it**: By default, Docker will use a locally cached image rather than looking for a newer image. This can be problematic when using a common base image like debian:jessie, since you may end up unintentionally using a very old base image.

I think everything here is only used on release paths, so it shouldn't affect any regular development workflows.

**Release note**:

```release-note
NONE
```