The `enrollment_end_date` parameter is accepted, but does nothing

[danielkberry]

We should fail CI validation when the enrollment_end_date parameter is passed, as passing that parameter does not cause the enrollment period to change. We should redirect users to the enrollment_period parameter.

Expected results:

[experiment]
enrollment_end_date = "2024-01-01"

This should fail CI validation

Actual results: passes validation

┆Issue is synchronized with this Jira Task