Use prebuilt package stored in intranet when possible and use
intranet mirror when git is required.
Task-number: QTQAINFRA-6903
Pick-to: 6.8 6.5 5.15
Change-Id: I1630098756c2e9b4f551686679e98a40af5eef2d
Reviewed-by: Simo Fält <simo.falt@qt.io>
(cherry picked from commit f23cd54e7f)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>