Bump DataScript dependency to 0.15.4.
Bump DataScript dependency to 0.15.4.

bgrins/datomish,mozilla/mentat,mozilla/mentat,ncalexan/mentat,ncalexan/mentat,mozilla/mentat,ncalexan/datomish,ncalexan/mentat,mozilla/mentat,bgrins/datomish,mozilla/mentat,ncalexan/mentat,ncalexan/mentat,ncalexan/mentat,ncalexan/datomish,mozilla/mentat