Remove PreferCache from network requests

Summary:
If we use PreferCache it means we never refresh the contents of the cache once we have it
so the user never sees changes like
https://cgit.kde.org/websites/edu-kde-org.git/commit/?id=27e250c2864f6aa4d71e9e938fe9f780966a4056

Reviewers: leinir

Reviewed By: leinir

Subscribers: Frameworks

Tags: Frameworks

Differential Revision: https://phabricator.kde.org/D8188