multi: make use of require.Len where possible

This commit changes instances of `require.Equal(t, <int>, len(<var>))`
to `require.Len(t, <var>, <int>)` where possible.

itest/assertions.go

@@ -1567,10 +1567,10 @@ func assertGroups(t *testing.T, client taprpc.TaprootAssetsClient,
 	require.NoError(t, err)
 
 	groupKeys := maps.Keys(assetGroups.Groups)
-	require.Equal(t, 2, len(groupKeys))
+	require.Len(t, groupKeys, 2)
 
 	groupedAssets := assetGroups.Groups[groupKeys[0]].Assets
-	require.Equal(t, 1, len(groupedAssets))
+	require.Len(t, groupedAssets, 1)
 	require.Equal(t, 1, len(assetGroups.Groups[groupKeys[1]].Assets))
 
 	groupedAssets = append(

tapdb/assets_store_test.go

@@ -1261,7 +1261,7 @@ func TestAssetExportLog(t *testing.T) {
 	// looking for all unconfirmed transfers.
 	assetTransfers, err := db.QueryAssetTransfers(ctx, TransferQuery{})
 	require.NoError(t, err)
-	require.Equal(t, 1, len(assetTransfers))
+	require.Len(t, assetTransfers, 1)
 
 	// We should also be able to find it based on its outpoint.
 	firstOutput := spendDelta.Outputs[0]
@@ -1270,7 +1270,7 @@ func TestAssetExportLog(t *testing.T) {
 		AnchorTxHash: firstOutputAnchor.OutPoint.Hash[:],
 	})
 	require.NoError(t, err)
-	require.Equal(t, 1, len(assetTransfers))
+	require.Len(t, assetTransfers, 1)
 
 	// Check that the new UTXO is found among our managed UTXOs.
 	utxos, err = assetsStore.FetchManagedUTXOs(ctx)
@@ -1302,13 +1302,13 @@ func TestAssetExportLog(t *testing.T) {
 		UnconfOnly: true,
 	})
 	require.NoError(t, err)
-	require.Equal(t, 1, len(assetTransfers))
+	require.Len(t, assetTransfers, 1)
 
 	// This should also show up in the set of pending parcels. It should
 	// also match exactly the inbound parcel we used to make the delta.
 	parcels, err := assetsStore.PendingParcels(ctx)
 	require.NoError(t, err)
-	require.Equal(t, 1, len(parcels))
+	require.Len(t, parcels, 1)
 	require.Equal(t, spendDelta, parcels[0])
 
 	// We should also be able to query for the parcel when filtering on its
@@ -1428,7 +1428,7 @@ func TestAssetExportLog(t *testing.T) {
 	// At this point, there should be no more pending parcels.
 	parcels, err = assetsStore.PendingParcels(ctx)
 	require.NoError(t, err)
-	require.Equal(t, 0, len(parcels))
+	require.Len(t, parcels, 0)
 }
 
 // TestAssetGroupWitnessUpsert tests that if you try to insert another asset