How to create custom Metering reports based on project labels

Issue

We've added several billing codes as labels to our projects and we want to aggregate these into the reports generated by openshift-metering.
Our cluster is fully disconnected and we can't make use of Red Hat Cost Management Solution.

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Here are the common uses of Markdown.

Code blocks

~~~
Code surrounded in tildes is easier to read
~~~

Links/URLs

[Red Hat Customer Portal](https://access.redhat.com)