Qt Quick Studio Components: Fix imports

[47/574 33.0/sec] Generating .rcc/qmlcache/QuickStudioComponents_BorderItem_qml.cpp
...
[48/574 33.5/sec] Generating .rcc/qmlcache/QuickStudioComponents_IsoItem_qml.cpp
Warning: IsoItem.qml:32:1: Warnings occurred while importing module "QtQuick.Extras": [import]
import QtQuick.Extras 1.4
^^^^^^
---
Warning: Failed to import QtQuick.Extras. Are your import paths set up properly? [import]
---

Warning: IsoItem.qml:65:1: Picture was not found. Did you add all import paths? [import]
Picture {
^^^^^^^
Info: IsoItem.qml:31:1: Unused import [unused-imports]
import QtQuick 2.9
^^^^^^
Info: IsoItem.qml:30:1: Unused import [unused-imports]
import QtQuick 2.0
^^^^^^
...
[49/574 33.8/sec] Generating .rcc/qmlcache/QuickStudioComponents_SvgPathItem_qml.cpp
Info: SvgPathItem.qml:31:1: Unused import [unused-imports]
import QtQuick.Timeline 1.0
^^^^^^