Fix event download

[virginiacc]

Fix issue that was preventing downloads on the event page.

Changes

• Only disable download modal button when privacy acknowledgment is required
• Add Cypress test for enabled download button on event page modal
• Add tests for downloaded data on Event and Evaluator pages
• Move privacy acknowledgment content to separate file

Testing

1. Front end tests should pass in PR checks
2. To manually validate, check out branch, navigate to event view, and verify that downloading works

[schbetsy]

I tested locally, and it looks fixed to me 👍