Support injecting GHRepository into an action method

[gsmet]

An action is always executed in the context of a repository so we could inject the GHRepository in the action method.

Best way to track how it work is to look at GitHubActionDotNames#INJECTABLE_TYPES references.

We should probably have a method lazily returning a GHRepository in GHEvent - the repository name is in the Context.

We will need to add some doc here: https://github.com/quarkiverse/quarkus-github-action/blob/main/docs/modules/ROOT/pages/developer-reference.adoc?plain=1#L106

[gsmet]

@gcw-it in case you're interested seeing other facets of Quarkus. Feel free to push back, you looked interested in experimenting so trying to push stuff to you :).

[gcw-it]

@gsmet I‘ll have very little time on my hands in the coming week, but since the task doesn‘t seem to be time critical, I‘ll see, what I can figure out. Should any questions arise regarding this task, would it be appropriate to create a draft PR, or what would you recommend?

[gsmet]

Ask here or create a draft PR.

And sure definitely not time critical and only take this if you’re interested and have time. No pressure.

[gcw-it]

No pressure perceived. I‘ll look into it as soon as time permits.