t5523-push-upstream: add function to ensure fresh upstream repo

Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5523-push-upstream.sh

@@ -3,8 +3,12 @@
 test_description='push with --set-upstream'
 . ./test-lib.sh
 
+ensure_fresh_upstream() {
+	rm -rf parent && git init --bare parent
+}
+
 test_expect_success 'setup bare parent' '
-	git init --bare parent &&
+	ensure_fresh_upstream &&
 	git remote add upstream parent
 '