Fix yq version specification

What does this MR do and why?

Pipeline jobs in the project are failing because we can no longer install yq: https://gitlab.com/gitlab-org/technical-writing-group/gitlab-docs-hugo/-/jobs/6701006178#L47

This MR fixes the install command to make sure we use yq version 4.x.

Merge request acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this merge request.