Create Installer 4.11 Qt Baseline: Qt 6.9.1

Create a Qt baseline for Installer 4.11:

• Qt version 6.9.1
• Squish 9.0.1
• MSVC compiler update from 2019 --> 2022

Updates need to be created to qt/tqtc-qt5 repository's tqtc/6.9.1 branch.

As a reference, see the updates done for earlier baseline 6.7.2: https://codereview.qt-project.org/q/project:qt/tqtc-qt5+branch:tqtc/6.7.2

As the msvc compiler changes, you probably need to rebuild 3rd party dependencies with the new compiler as well.