Fix broken url for og:image tag for rich previews
Fix broken url for og:image tag for rich previews

Spotted that the link to an image for rich previews was using .com rather than .co.uk and hence returning a completly different (and wrong) image.

This change fixes the typo.

Cruikshanks/cruikshanks.github.io,Cruikshanks/cruikshanks.github.io