Fix KProtocoInfoTest if krusader is installed
Summary:
Krusader has a krarc ioslave that handles zip files. If krusader is
installed, testProtocolForArchiveMimetype randomly fails depending on
the order the zip and krarc protocols are added to the cache.
This patch makes sure the test always passes.
Test Plan: Run kprotocolinfotest with krusader installed.
Reviewers: dfaure, davidedmundson
Reviewed By: davidedmundson
Subscribers: ngraham, Frameworks
Tags: Frameworks
Differential Revision: https://phabricator.kde.org/D8698