Update boskos pool dashboard to support same type, different instance

[spiffxp]

I would like to have pools named identically across prow-builds' boksos
and k8s-infra's boskos, so there's one less thing to change when
migrating a prowjob from one build cluster to the other.

k8s-infra-gce-project vs. gce-project was a mistake I'd like to undo

I also want to be able to display a panel per-instance for the same pool
type. This is the dumb hardcoded approach

[spiffxp]

I added 5 projects to the k8s-infra boskos instance ref: kubernetes/k8s.io#898

[cjwagner]

This looks correct to me.
One alternative/improvement to consider would be making the instance a template variable to avoid hardcoding and make it easy to filter the list of graphs by instance (e.g. this dashboard).
/hold

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cjwagner, spiffxp

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• config/prow/cluster/monitoring/OWNERS [cjwagner,spiffxp]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[spiffxp]

making the instance a template variable to avoid hardcoding

I agree, but I'd like the "all" option to enumerate dashboards, instead of aggregate. I think there's value in seeing one pool go down and the other go up side-by-side. I'll work on getting a setup where I can dev/test this locally. And I'll need to migrate k8s-infra-gce-project into gce-project.

[BenTheElder]

/lgtm

[spiffxp]

/hold cancel