115 - Create use case to get a file

[MellyGray]

What this PR does / why we need it:

This PR adds a new use case getFile to the module to get a file given its id or persistentId and an optional datasetVersion.

Which issue(s) this PR closes:

• Closes Create use case to get a file #115

Related Dataverse PRs:

• Depends on #

Special notes for your reviewer:

The API needs to be extended to accept the datasetVersion parameter, so for the moment this use case will throw a Not Implemented Yet error when the user specifies a datasetVersion different than draft or latest.

Suggestions on how to test this:

1. Visual inspection of the code
2. Check unit and integration tests execution in GitHub actions

Is there a release notes update needed for this change?

getFile use cases added to the module to get a file given its id or persistentId and an optional datasetVersion

Additional documentation:

[ekraffmiller]

This looks good! I just have questions about how we will handle versioning.

[MellyGray]

@ekraffmiller, I think I might need to assign this to myself again after reading this explanation. It seems that files do not have versions. Therefore, fileVersionId should be renamed to dataverseVersionId in the GetFile use case

[ekraffmiller]

The addition of datasetVersion parameter looks good, approved! Thanks for clarifying that.

[GPortas]

@MellyGray Can you please solve merge conflicts?

[GPortas]

LGTM