satellite/durability: report bus_factor with the new reports

New instance based satellites are reporting durability alerts like `class=last_net, value=192.168.0.0`.

Bus factor will be reported as `class=bus_factor value=last_net`.

Change-Id: I0130866fa8e50b3d2876f580a78383bb1c609159

satellite/durability/observer.go

@@ -208,6 +208,7 @@ func (c *Report) Finish(ctx context.Context) error {
 	for name, stat := range c.healthStat {
 		c.reporter(reportTime, c.class, name, stat)
 	}
+	c.reporter(reportTime, "bus_factor", c.class, &c.busFactor)
 	return nil
 }
 

satellite/durability/observer_integration_test.go

@@ -67,7 +67,7 @@ func TestDurabilityIntegration(t *testing.T) {
 		_, err := rangedLoopService.RunOnce(ctx)
 		require.NoError(t, err)
 
-		require.Len(t, result, 15)
+		require.Len(t, result, 19)
 		// one or two pieces are controlled out of the 5-6 --> 3 or 4 pieces are available without HU nodes
 		require.Equal(t, result["HU"].Min(), 4)