Bump govuk_content_models and gds-api-adapters

Bump govuk_content_models in order to get the new manual and
manual-section formats.

Bump gds-api-adapters because govuk_content_models now depends on a more
recent version.

Tag IDs are now validated in govuk_content_models to only allow slashes
for child tags. This commit updates all the tests affected by that
change.
Attach editions for all specialist-publisher artefacts

Manual and manual-section artefacts should have editions attached too,
in addition to specialist-document artefacts.
Merge pull request #180 from alphagov/handle-manual-artefacts

Handle manual artefacts