ls: fix recent regression in size alignment

* src/ls.c (print_long_format): Use correct column width,
introduced due to a copy/paste error in commit v9.4-2-gcbb6dfec5
* tests/ls/size-align.sh: Add a test.
* tests/local.mk: Reference the new test.
Fixes https://bugs.gnu.org/66919

tests/ls/size-align.sh

@@ -0,0 +1,32 @@
+#!/bin/sh
+# test size alignment
+
+# Copyright (C) 2023 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ ls truncate
+
+truncate -s      0 small || framework_failure_
+truncate -s 123456 large || framework_failure_
+echo > alloc || framework_failure_
+
+ls -s -l small alloc large > out || fail=1
+len=$(wc -L < out) || framework_failure_
+lines=$(wc -l < out) || framework_failure_
+same=$(grep "^.\\{$len\\}\$" out | wc -l) || framework_failure_
+test "$same" = "$lines" || { cat out; fail=1; }
+
+Exit $fail