Enhancement: Allow to query workflow runs against multiple repositories at once

My goal is to have a centralised (one per a whole Github ORG) dashboard with all workflow runs in the whole organisation.

In order to query workflow runs the following parameters are needed:
- Github ORG name - this is a static value basically
- repository name - it's easy to get all repositories across the ORG using a separate query
- workflow filename - it is problematic to get list of workflow filenames dynamically, however most of my workflow filenames are the same, so I can work with that and hardcode this value
- (branch name is optional)

Based on that we have all elements we need, however a query to Github API can use only one parameter, so we can query a single org-repo-filename combination at once.

So I was thinking that maybe the plugin can detect if multiple repository names are provided and break the query into multiple sub-queries in order to return the results? This is more or less how Prometheus datasource plugin works when multiple values are selected from the dropdown boxes (eg. query for CPU usage in VM1, VM2, VM3).

I'm happy to discuss alternative solutions as well. Many thanks in advance!

Inizia con la richiesta GitHub API per workflow-runs descritta nell’issue e verifica dove la selezione dei repository diventa una query; il payload non indica file né test. Il lavoro è completato quando una dashboard può selezionare più repository e ricevere risultati combinati delle esecuzioni dei workflow, mantenendo l’organizzazione, il nome del file del workflow e gli input opzionali del branch.

Scritto dal modello di indicizzazione a partire dal testo della issue.