Use classic static.guim.co.uk as original image for articles if possible

Trawling forums indicates that it is possible that Google News does not pick up images from a CDN https://productforums.google.com/forum/#!topicsearchin/news/cdn$20images

It seems possible it only picks up images from domains it trusts (e.g. over time, or it has been asked to trust them).

We know it picks up images from static.guim.co.uk, so this is a test to check that hypotheses.

It will only use static.guim.co.uk if there is an exact match for the width.

Image upgrades still work.