Validation of forecast submissions prior to submitting to forecast hub

[kaitejohnson]

Problem

We do not have local CI in place in the production pipeline to catch the checks in the COVID Forecast Hub repo. This would make it easier to ensure all of our submissions will pass the flags they have

Context

From @swo: I poked briefly at this:

• Their software as written doesn't do anything when run locally: https://github.com/reichlab/covid19-forecast-hub-validations/blob/main/main.py#L167
• The target repo needs to have a project-config.json file (that filename is hardcoded): https://github.com/reichlab/covid19-forecast-hub/blob/master/project-config.json
• It's not clear to me that this actually look at any local files, or if it only points to a GitHub-hosted repo and its PRs @ seabbs: COuld be a good use case to open an issue on their repo