sweepbatcher/Store: do not provide LoopOut field

This data is not used by Batcher since commit
"sweepbatcher: load swap from loopdb, not own store".

Now sweepbatcher.Store depends only on tables sweeps and sweep_batches
and does not depend on swaps, loopout_swaps and htlc_keys, making it
easier to reuse.

loopdb/sqlc/queries/batch.sql

@@ -91,22 +91,13 @@ AND
 
 -- name: GetBatchSweeps :many
 SELECT
-        sweeps.*,
-        swaps.*,
-        loopout_swaps.*,
-        htlc_keys.*
+        *
 FROM
         sweeps
-JOIN
-        swaps ON sweeps.swap_hash = swaps.swap_hash
-JOIN
-        loopout_swaps ON sweeps.swap_hash = loopout_swaps.swap_hash
-JOIN
-        htlc_keys ON sweeps.swap_hash = htlc_keys.swap_hash
 WHERE
-        sweeps.batch_id = $1
+        batch_id = $1
 ORDER BY
-        sweeps.id ASC;
+        id ASC;
 
 -- name: GetSweepStatus :one
 SELECT