Specify matching ids for blockage_migration

src/proto/blockage_migration.rs

@@ -53,6 +53,7 @@ muCMZProtocol! { blockage_migration,
     [ L: Lox { id: R, bucket: H, trust_level: R, level_since: H, invites_remaining: H, blockages: H },
     M: Migration { lox_id: R, from_bucket: H, to_bucket: H } ],
     N: Lox {id: J, bucket: H, trust_level: I, level_since: S, invites_remaining: I, blockages: H },
+    L.id = M.lox_id,
     L.bucket = M.from_bucket,
     N.bucket = M.to_bucket,
     N.blockages = L.blockages + 1,