Move `au.org.access-nri/model/reproducibility` into `au.org.access-nri/model/configuration`

[CodeGat]

We might not have thought about the directory structure enough with our schema repository. We will be adding a model/configuration directory as part of #32 and it seems that reproducibility would be better placed under model/configuration/reproducibility.

Would need to update workflows that use the old path, if we do update this.

Pinging @aidanheerdegen for advice on this change.