Fix the `qa_agent_ot` GitLab job

[L3n41c]

What does this PR do?

Fix the qa_agent_ot GitLab job.

Motivation

The tag of the docker image consumed by qa_agent_ot here: https://github.com/DataDog/datadog-agent/blob/04c5db04f035dbe33040df6e8a005dcfc03945e8/.gitlab/dev_container_deploy/docker_linux.yml#L298 needs to match the tag of the docker images produced by the dependencies declared here: https://github.com/DataDog/datadog-agent/blob/04c5db04f035dbe33040df6e8a005dcfc03945e8/.gitlab/dev_container_deploy/docker_linux.yml#L294-L295 and when we look at those jobs here: https://github.com/DataDog/datadog-agent/blob/04c5db04f035dbe33040df6e8a005dcfc03945e8/.gitlab/container_build/docker_linux.yml#L197 and there: https://github.com/DataDog/datadog-agent/blob/04c5db04f035dbe33040df6e8a005dcfc03945e8/.gitlab/container_build/docker_linux.yml#L211 we see that the -beta part of the suffix seems to be missing.

Additional Notes

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes