t5319: use 'test-tool path-utils' instead of 'ls -l'

Using 'ls -l' and parsing the columns to find file sizes is
problematic when the platform could report the owner as a name
with spaces. Instead, use the 'test-tool path-utils file-size'
command to list only the sizes.

Reported-by: Johannes Sixt <j6t@kdbg.org>
Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: derrickstolee

t/t5319-multi-pack-index.sh

@@ -443,7 +443,7 @@ test_expect_success 'repack with minimum size does not alter existing packs' '
 		touch -m -t 201901010002 .git/objects/pack/pack-B* &&
 		touch -m -t 201901010003 .git/objects/pack/pack-A* &&
 		ls .git/objects/pack >expect &&
-		MINSIZE=$(ls -l .git/objects/pack/*pack | awk "{print \$5;}" | sort -n | head -n 1) &&
+		MINSIZE=$(test-tool path-utils file-size .git/objects/pack/*pack | sort -n | head -n 1) &&
 		git multi-pack-index repack --batch-size=$MINSIZE &&
 		ls .git/objects/pack >actual &&
 		test_cmp expect actual
@@ -455,7 +455,7 @@ test_expect_success 'repack creates a new pack' '
 		cd dup &&
 		ls .git/objects/pack/*idx >idx-list &&
 		test_line_count = 5 idx-list &&
-		THIRD_SMALLEST_SIZE=$(ls -l .git/objects/pack/*pack | awk "{print \$5;}" | sort -n | head -n 3 | tail -n 1) &&
+		THIRD_SMALLEST_SIZE=$(test-tool path-utils file-size .git/objects/pack/*pack | sort -n | head -n 3 | tail -n 1) &&
 		BATCH_SIZE=$(($THIRD_SMALLEST_SIZE + 1)) &&
 		git multi-pack-index repack --batch-size=$BATCH_SIZE &&
 		ls .git/objects/pack/*idx >idx-list &&