This Dockerfile should be based on the already existing docker files.
The discovery / search / query service team should be contacted regarding the contents of RWStore.properties for the snapshot.
The latest versions can be used from https://archiva.wikimedia.org/repository/releases/org/wikidata/query/rdf/service/ (0.3.40 at the time of writing this)
Their (search team) review should also be sought for the PR introducing the new image.
This code lives in: https://github.com/wmde/wikibase-docker
Docs for updating / releasing new images https://github.com/wmde/wikibase-docker/tree/master/wdqs#development
The search team can be found on IRC on freenode in the "wikimedia-discovery" channel and are available in EU daytime.