Setting `evil-ex-search-persistent-highlight` to `nil` does not clear highlight when pressing `n` or `N`

[Sjmarf]

I've got evil-search-module set to evil-search.

If I set evil-ex-search-persistent-highlight to nil, the highlight (correctly) goes away when I conclude a search by pressing return. However, when I press n or N, the highlight returns and remains permanently. I'd like a way to configure this such that it has the same behaviour as isearch: when n is pressed, show the highlight until the cursor is moved. This could be implemented by changing how evil-ex-search-persistent-highlight behaves, or by adding a new configuration variable.