Add query scheduler to "Read Resources" mixin dashboard (#6028)

This component has been around for a while but has not been added to the
loki-mixin yet.

Signed-off-by: Christian Haudum <christian.haudum@gmail.com>

production/loki-mixin/dashboards/loki-reads-resources.libsonnet

@@ -32,6 +32,18 @@ local utils = import 'mixin-utils/utils.libsonnet';
             $.goHeapInUsePanel('Memory (go heap inuse)', 'query-frontend'),
           )
         )
+        .addRow(
+          $.row('Query Scheduler')
+          .addPanel(
+            $.containerCPUUsagePanel('CPU', 'query-scheduler'),
+          )
+          .addPanel(
+            $.containerMemoryWorkingSetPanel('Memory (workingset)', 'query-scheduler'),
+          )
+          .addPanel(
+            $.goHeapInUsePanel('Memory (go heap inuse)', 'query-scheduler'),
+          )
+        )
         .addRow(
           $.row('Querier')
           .addPanel(