Would recommend “Implement HTTPS” as the task title.
User stories are great for describing a problem, particularly from a customer point of view (or in the shoes of a customer). They also help customers structure their problems so that they less likely to put forward what they think is a solution.
But you need to be practical, that’s part of the agile manifesto.
There’s no misunderstanding of the problem here; there’s no great interpretation and there’s no “open-mindedness” required. A user story could actually muddy an otherwise clear outcome in this instance.
Do yourself and your team a favour by keeping this simple. But definitely log, track and create a definition of done, so it can be tested and qa’dsized.