Fix gui freezes caused by polish loop

[XINJIANGMO]

🦟 Bug fix

Fixes #3154

Summary

In the implementation of Qt6, the content item QQuickPopupItem of the Popup will interact with the x/y contentItem.width/height binding during the measurement and positioning stage, resulting in polish loop.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
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• All tests passed (See test coverage)
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[iche033]

I couldn't reproduce the issue following the steps in #3154. When simulation is running, a dialog pops up asking me to pause simulation (as expected). I also tested the changes in this PR and noticed that the dialog now pops up in a different place but immediately moves to the specified position.

Maybe someone else can also try and see if the. GUI freezes for them

[XINJIANGMO]

I couldn't reproduce the issue following the steps in #3154. When simulation is running, a dialog pops up asking me to pause simulation (as expected). I also tested the changes in this PR and noticed that the dialog now pops up in a different place but immediately moves to the specified position.

Maybe someone else can also try and see if the. GUI freezes for them

I copy the ComponentInspectorEditor.qml in gz-sim10 branch and compile again. I am sure that I can reproduce this issue. Maybe someone else can also try and see if the GUI freezes for them.