HdMergingSceneIndex issue with RemoveInputScene.

[Lumengine]

Description of Issue

Crash when deleting the _MergingSceneIndexEntry from UsdImagingNiPrototypePropagatingSceneIndex.

With this commit 2ee856c, when refactoring the RemoveInputScene, the line

std::vector<SdfPath> removalTestQueue = { it->sceneRoot };

is created after erasing the iterator which causes the crash.

Steps to Reproduce

System Information (OS, Hardware)

Windows 11

Package Versions

v24.11

Build Flags

[jesschimein]

Filed as internal issue #USD-10375