Improve submodule update performance significantly

This commit add the usage of shallow submodule updates. Thus after
checking out the targeted commit of the parent repository only the
required commits of the submodules are fetched.

1 files changed, 1 insertions, 0 deletions

diff --git a/main.go b/main.go
index 9020aaa..505daf1 100644
--- a/main.go
+++ b/main.go
@@ -83,6 +83,7 @@ func prepareWorkbench(repo string, commit string) string {
 		workbench,
 		"submodule",
 		"update",
+		"--depth=1",
 		"--init",
 		"--recursive",
 	)