Release dummy wheel listener on workspace dispose

[ananta]

The basics

• I validated my changes

The details

Resolves

Fixes #7674

Proposed Changes

• Introduced a new class member dummyWheelListener in WorkspaceSvg to store the dummy wheel event listener.
• Modified the dispose method in WorkspaceSvg to remove the dummyWheelListener from the document body when the workspace is disposed.

Reason for Changes

Previously, the dummy wheel event listener added to the document as a workaround for a Safari bug was not being properly disposed of. This could potentially lead to memory leaks and unintended behavior. By storing the listener in a class member, we can ensure it is correctly removed when the workspace is disposed, thus improving the robustness and cleanliness of the code.

Test Coverage

• Manually tested to confirm that the dummyWheelListener is added and removed correctly.
• Ensured that the addition and removal of this listener have no side effects on the functionality of WorkspaceSvg.

Documentation

• No major documentation updates required as these changes are internal and pertain to fixing a specific bug.

Additional Information

N/A

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[BeksOmega]

This looks great =) Thank you for the fix! Once CI passes I'll get this merged.