Update config.yml
Update config.yml

At -{{ arch }} to the cache keys
Because of https://discuss.circleci.com/t/changes-in-the-processor-architecture-for-the-docker-executor-on-circleci/25584

This is likely required for the GCH cache. I am not so sure about the Haskell dependencies but it also shouldn't hurt as these kinds of changes should be rare.
rTreutlein/atomspace,rTreutlein/atomspace,AmeBel/atomspace,rTreutlein/atomspace,AmeBel/atomspace,AmeBel/atomspace,rTreutlein/atomspace,AmeBel/atomspace,rTreutlein/atomspace,AmeBel/atomspace