Extract project version

[LecrisUT]

Would be useful to automatically extract and store the project version to a variable. This should be done via FileApi to ensure that it is set even if it is dynamically defined outside project().

Usage I think it is obvious in that it is for uploading tags and github releases.

[lukka]

@LecrisUT thanks for the suggestion! Are you willing to create a PR for adding the feature?
Some thoughts:

• this may be a specific action that could be accomplishing this task, but also a nice to have feature in run-cmake.
• are there bindings to use the FileApi from TypeScript/JavaScript?

[LecrisUT]

Fileapi here refers to cmake-file-api. It basically imvolves running cmake configuration with a specific json file. That's why it would make sense to have it here, to consolidate the multiple cmake configuration runs into 1.

Unfortunately I don't have experience in writing github actions and I couldn't deduce my way out of the current implementation, so probably I can't make a PR for this.