[thanos] - remove thanos-staging gstg and pre sidecars
What
- removes the sidecars for
gstg
andpre
from thanos-staging queriers.
Why
gstg
and pre
now have a remote write prometheus instance deployed, and this removes the need to query the instances directly.
As this is currently experimental, this is just applied to the staging thanos.
Related Issue: https://gitlab.com/gitlab-com/gl-infra/reliability/-/issues/24515