Grafana: clean up OVH graphs

I missed some tweaks on the previous Test Nodes graph change.

Also make the job runtimes wider like Paul suggested.

Change-Id: I5ac43909a679d273a557112ad8526a68de15f4f1

grafana/nodepool-ovh.yaml

@@ -120,6 +120,7 @@ dashboard:
           stack: true
           tooltip:
             value_type: individual
+          leftYAxisLabel: "nodes"
           targets:
             - target: alias(stats.gauges.nodepool.provider.ovh-bhs1.nodes.building, 'Building')
             - target: alias(stats.gauges.nodepool.provider.ovh-bhs1.nodes.ready, 'Available')
@@ -128,6 +129,9 @@ dashboard:
         - title: Test Nodes (GRA1)
           type: graph
           span: 4
+          stack: true
+          tooltip:
+            value_type: individual
           leftYAxisLabel: "nodes"
           targets:
             - target: alias(stats.gauges.nodepool.provider.ovh-gra1.nodes.building, 'Building')
@@ -140,7 +144,7 @@ dashboard:
       panels:
         - title: gate-tempest-dsvm-full
           type: graph
-          span: 4
+          span: 6
           leftYAxisLabel: "time"
           y_formats:
             - s
@@ -150,7 +154,7 @@ dashboard:
             - target: alias(scale(stats.timers.nodepool.job.gate-tempest-dsvm-full.master.devstack-trusty.ovh-gra1.runtime.mean, '0.001'), 'GRA1')
         - title: gate-tempest-dsvm-neutron-full
           type: graph
-          span: 4
+          span: 6
           leftYAxisLabel: "time"
           y_formats:
             - s