PBR refractionIntensityTexture in the inspector

[sebavan]

https://forum.babylonjs.com/t/refractionintensitytexture-is-not-being-displayed-in-the-inspector/30697

[azure-pipelines]

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[azure-pipelines]

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Test environment:
https://babylonsnapshots.z22.web.core.windows.net/refs/pull/12572/merge/index.html

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