Fix double globe when lighting is enabled

[OmarShehata]

In CesiumJS 1.63, try running:

var viewer = new Cesium.Viewer('cesiumContainer');
viewer.scene.globe.enableLighting = true

You'll get a double globe:

You can fix this by going back to the old resolution scale behavior we had in 1.61:

viewer.resolutionScale = 1.0 / window.devicePixelRatio;

This happens because in #8318 we added a multiplication by czm_pixelRatio in metersPerPixel.glsl. This caused a second globe to render at half the size when globe lighting was enabled. This fixes it by dividing back by that value. But I'm not sure if this is the right fix. @lilleyse @IanLilleyT what do you think?

@mramato is this worth a 1.63.1 patch release?

This was reported on the forum.

[cesium-concierge]

Thanks for the pull request @OmarShehata!

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[mramato]

@mramato is this worth a 1.63.1 patch release?

The bar for a patch release is usually pretty high, since this only happens with lighting enabled, only on machines that have devicePixelRatio !== 1, and has an easy workaround, I don't think doing a release is warranted unless we find out it affects a large piece of the community.

I would love to move to more frequent CesiumJS releases in general, but that's a larger conversation.

[IanLilleyT]

@OmarShehata I have a related fix that also affects labels. So once that's up we can merge mine and close this one.

[IanLilleyT]

Here's the PR that fixes the globe lighting and labels: #8351

[lilleyse]

Superseded by #8351