t7003: make test repeatable

Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t7003-filter-branch.sh b/t/t7003-filter-branch.sh
index 9a4dae4..c82ff1d 100755
--- a/t/t7003-filter-branch.sh
+++ b/t/t7003-filter-branch.sh
@@ -7,6 +7,7 @@
 	lower=$(echo $1 | tr A-Z a-z)
 	echo $lower > $lower
 	git add $lower
+	test_tick
 	git commit -m $1
 	git tag $1
 }