Update various things in the build image

[sylr]

What this PR does:

Which issue(s) this PR fixes:
Fixes #

Checklist

• Tests updated
• Documentation added
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]

[bboreham]

I changed the title since we have a few "Dockerfile"s

[pracucci]

I've published for your the Docker image quay.io/cortexproject/build-image:dockerfile-3860bbe9-WIP based on the updated build-image/Dockerfile. May you rebase master, replace the image URL in .circleci/config.yml and push it, so that we can test if the CI pass?

[pracucci]

For the records, the new build-image (dockerfile-3860bbe9-WIP) is 32MB bigger then the current one (validate-k8s-specs-7c217ee7). Not dramatic, but worth to note.

[pracucci]

I've published for your the Docker image quay.io/cortexproject/build-image:dockerfile-3860bbe9-WIP [...] Can you [...] replace the image URL in .circleci/config.yml and push it, so that we can test if the CI pass?

May you also address this, please?

[sylr]

@pracucci do you know what should be done to pass CI ?

[pracucci]

Let me try to push changes directly to this PR, to contribute to make this PR into a mergeable state.

[gouthamve]

Superseded by #2480