@actions/core Provide way to get pull request opener in the Context.

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Describe the enhancement
A clear and concise description of what the features or enhancement you need.
I would like this for easier porting of ruby code to js to support Windows and OSX and drop docker unless you guys plan to enable use of ruby on OSX and Windows by using an action to set it up first so that way said actions can be executed properly.

Code Snippet
If applicable, add a code snippet to show the api enhancement.
Not sure how it would work, however I would like this added to the body of the Context.

Additional information
Add any other context about the feature here.
Take a look at this example ruby code, I would like to port this to JS to support Windows and OSX as well: https://github.com/Elskom/merge-dependabot/blob/main/entrypoint.sh

Start by reading the @actions/core Context API and compare the requested pull-request opener with the linked merge-dependabot entrypoint.sh example. Clarify how the opener should be exposed and what context data is available before deciding the API shape. Done means callers can reliably access the pull request opener in supported environments.