Ignore ruby updates in Docker
Ignore ruby updates in Docker

We need to upgrade Ruby in a very specific way - it
is not helpful for Dependabot to raise upgrade PRs
for us. Therefore we have put 'ruby' on the ignore

list.

Trello: https://trello.com/c/uPoriyfJ/2049-add-dependabot-configuration-to-each-repo-blitz-pair

alphagov/asset-manager,alphagov/asset-manager,alphagov/asset-manager