Add support for dashboards datasource filter (#2560)

This commit add support for dashboards datasource filter using a regex named 'datasource_regex'
provided in the config.libsonnet file.

It's done in a similar way than for grafana/mimir.

Signed-off-by: julien.girard <[email protected]>

Author: bubu11e

operations/pyroscope/jsonnet/pyroscope-mixin/pyroscope-mixin/config.libsonnet

@@ -14,5 +14,7 @@
     // Add the mixin with support for multiple cluster
     multi_cluster: true,
 
+    // Regex used to filter proposed datasources
+    datasource_regex: '',
   },
 }

operations/pyroscope/jsonnet/pyroscope-mixin/pyroscope-mixin/dashboards/dashboard-utils.libsonnet

@@ -5,7 +5,11 @@ local utils = import 'mixin-utils/utils.libsonnet';
   // - default tags,
   // - some links that propagate the selected cluster.
   dashboard(title, uid='')::
-    super.dashboard(title, uid) + {
+    super.dashboard(
+      title,
+      uid,
+      datasource_regex=$._config.datasource_regex
+    ) + {
       addRowIf(condition, row)::
         if condition
         then self.addRow(row)