Add Reference Date Payload From Ensemble Workflow To Report Dispatch Workflow

This issue covers taking the `reference_date` object in `./github/workflow/create-ensemble.yaml` and having it payloaded into `./github/workflow/dispatch-covidhub-reports.yaml` so that users do not manually have to enter the reference date again when <https://github.com/CDCgov/covidhub-reports/blob/main/.github/workflows/generate-visualization-data.yaml> is ran.