GeoTIFF images without overviews cause an exception in GeoTIFFSource

Summary

Steps to reproduce

1. Create a GeoTIFFSource that points to a GeoTIFF without overviews, for example https://github.com/mommermi/geotiff_sample/blob/master/sample.tif

Expected behaviour:

The image is displayed correctly.

Actual behaviour:

An exception is raised:

Uncaught TypeError: image is undefined
    adjustExtentAndPixelSize GeoTIFFSource.js:251
    adjustExtentAndPixelSize Layer.js:616
    update Layer.js:870
    postUpdate Map.js:1060
    postUpdate Map.js:1060
    traverseTiles Map.js:1376
    traverse three.module.js:7761
    traverse three.module.js:7767
    traverseTiles Map.js:1374
    postUpdate Map.js:1058
    update MainLoop.js:117
    step MainLoop.js:209
    scheduleUpdate MainLoop.js:80
    scheduleUpdate MainLoop.js:79
    notifyChange Instance.js:408
    add Instance.js:367
    run geotiff_test.js:42
    js geotiff_test.js:66
    Webpack 7

Informations

• Giro3D version: 0.41
• Browser (Firefox, Chrome, Opera, Safari...) and version: N/A
• OS (Linux, MacOS, Windows...) N/A