frontend: Fix startup crash in qwindows.dll on Windows 11 24H2 with OBS 32.0.2 and 31.x portable

[wanhongqing123]

Description

Fix startup crash in qwindows.dll on Windows 11 24H2 with OBS 32.0.2 and 31.x portable

Motivation and Context

Please issue: #12829.

Replace the system WS_EX_ACCEPTFILES property with the setAcceptDrops method from Qt.

See: https://doc.qt.io/qt-6/qwidget.html#acceptDrops-prop

How Has This Been Tested?

I have tested in my complute.

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.