scalar-diagnose: use "$GIT_UNZIP" in test

Use the "$GIT_UNZIP" test variable rather than verbatim 'unzip' to unzip the
'scalar diagnose' archive. Using "$GIT_UNZIP" is needed to run the Scalar
tests on systems where 'unzip' is not in the system path.

Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/scalar/t/t9099-scalar.sh

@@ -109,14 +109,14 @@ test_expect_success UNZIP 'scalar diagnose' '
 	sed -n "s/.*$SQ\\(.*\\.zip\\)$SQ.*/\\1/p" <err >zip_path &&
 	zip_path=$(cat zip_path) &&
 	test -n "$zip_path" &&
-	unzip -v "$zip_path" &&
+	"$GIT_UNZIP" -v "$zip_path" &&
 	folder=${zip_path%.zip} &&
 	test_path_is_missing "$folder" &&
-	unzip -p "$zip_path" diagnostics.log >out &&
+	"$GIT_UNZIP" -p "$zip_path" diagnostics.log >out &&
 	test_file_not_empty out &&
-	unzip -p "$zip_path" packs-local.txt >out &&
+	"$GIT_UNZIP" -p "$zip_path" packs-local.txt >out &&
 	grep "$(pwd)/.git/objects" out &&
-	unzip -p "$zip_path" objects-local.txt >out &&
+	"$GIT_UNZIP" -p "$zip_path" objects-local.txt >out &&
 	grep "^Total: [1-9]" out
 '