Incorrect information in Google scene of Cesium for Unity Samples

[kring]

Scene 07_CesiumGoogleMapsTiles has this billboard:

This text should be updated, because I don't think it's Experimental anymore, and you can now access it via Cesium ion.

[j9liu]

I'm transferring this to cesium-unity-samples because it's more relevant to the sample project itself. But let me know if you prefer it on the cesium-unity repo instead!