[frontend] Send all the metrics to the same channel

Instead of having one routing key / channel for each metric we are now
sending all to "opensuse.obs.metrics"

Co-authored-by: Ana María Martínez Gómez <ammartinez@suse.de>
Co-authored-by: David Kang <dkang@suse.com>

contrib/telegraf.conf

@@ -106,7 +106,7 @@
   ## AMQP queue name
   queue = ""
   ## Binding Key
-  binding_key = "#"
+  binding_key = "opensuse.obs.metrics"
 
   ## Maximum number of messages server should give to the worker.
   prefetch_count = 50

src/api/app/models/event/base.rb

@@ -272,7 +272,7 @@ def _roles(role, project, package = nil)
 
     def send_to_bus
       RabbitmqBus.send_to_bus(self.class.message_bus_routing_key, self[:payload])
-      RabbitmqBus.send_to_bus("metrics.#{self.class.message_bus_routing_key}", to_metric) if metric_fields.present?
+      RabbitmqBus.send_to_bus('metrics', to_metric) if metric_fields.present?
     end
 
     private