Mixin: Add Query Frontend grafana dashboard (#4856)

* Add queryFrontend selector, start dashboard

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Fix naming, generate query_frontend.json

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Add resources row

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Add cache row, fe queries panel

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Update mixin README

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Solve conflicts

Signed-off-by: Jéssica Lins <jlins@redhat.com>

* Change to queryFrontend instead of query_frontend

Signed-off-by: Jéssica Lins <jlins@redhat.com>

CHANGELOG.md

@@ -24,7 +24,7 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 - [#4576](https://github.com/thanos-io/thanos/pull/4576) UI: add filter compaction level to the Block UI.
 - [#4731](https://github.com/thanos-io/thanos/pull/4731) Rule: add stateless mode to ruler according to https://thanos.io/tip/proposals-accepted/202005-scalable-rule-storage.md/. Continue https://github.com/thanos-io/thanos/pull/4250.
 - [#4612](https://github.com/thanos-io/thanos/pull/4612) Sidecar: add `--prometheus.http-client` and `--prometheus.http-client-file` flag for sidecar to connect Prometheus with basic auth or TLS.
-- [#4848](https://github.com/thanos-io/thanos/pull/4848) Compactor: added Prometheus metric for tracking the progress of retention.
+- [#4856](https://github.com/thanos-io/thanos/pull/4856) Mixin: Add Query Frontend Grafana dashboard.
 
 ### Fixed
 

examples/dashboards/dashboards.md

@@ -5,6 +5,7 @@ There exists Grafana dashboards for each component (not all of them complete) ta
 - [Thanos Overview](overview.json)
 - [Thanos Compact](compact.json)
 - [Thanos Querier](query.json)
+- [Thanos Query Frontend](queryFrontend.json)
 - [Thanos Store](store.json)
 - [Thanos Receiver](receive.json)
 - [Thanos Sidecar](sidecar.json)