Unhide the foreign-store package so that stack ghci works without errors

package.yaml

@@ -50,6 +50,7 @@ dependencies:
 - blaze-markup >=0.8 && <0.9
 - conduit-combinators >= 1.1 && < 1.2
 - friendly-time >=0.4 && < 0.5
+- foreign-store >=0.2 && <0.3
 - libravatar >=0.4 && <0.5
 - slug >=0.1 && <0.2
 - split >=0.2 && <0.3