Create a metric for counting Packit requests per project

[majamassarini]

So that we can have a better understanding of the rate-limit issues we have.

We want to track the requests we do per project.
The idea is described here (approach 1). It should be applied to all the services not only Github.

To implement it we can, for example, inject the Prometeus objects into the Ogr services classes and increase a counter for every request in ogr.