fix shaky Windows blackbox tests
fix shaky Windows blackbox tests

On our Windows test machine a timeout of 30 s is not enough.
Set timeout to five minutes.

Change-Id: Icbc719390f57d33c86fe828a209f3c6fa3ca5f9e
Reviewed-by: Christian Kandeler <3aa99dcdd3f0cac61fb81c2a11771c0cc2497607@digia.com>

Distrotech/qbs,gatzka/qt-labs-qbs,gatzka/qt-labs-qbs,qt-labs/qbs,qt-labs/qbs,qtproject/qt-labs-qbs,qtproject/qt-labs-qbs,gatzka/qt-labs-qbs,gatzka/qt-labs-qbs,villytiger/qbs,qtproject/qt-labs-qbs,gatzka/qt-labs-qbs,qt-labs/qbs,qt-labs/qbs,Distrotech/qbs,Distrotech/qbs,villytiger/qbs,villytiger/qbs,Distrotech/qbs,qt-labs/qbs,Distrotech/qbs,qtproject/qt-labs-qbs,qtproject/qt-labs-qbs,Distrotech/qbs,qtproject/qt-labs-qbs,qt-labs/qbs,gatzka/qt-labs-qbs,qtproject/qt-labs-qbs,Distrotech/qbs,qt-labs/qbs,villytiger/qbs,gatzka/qt-labs-qbs,villytiger/qbs,villytiger/qbs