lib/repo-pull: Add more debugging on pull failure

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Closes: #1925
Approved by: cgwalters

src/libostree/ostree-repo-pull.c

@@ -385,6 +385,8 @@ check_outstanding_requests_handle_error (OtPullData          *pull_data,
   GError *error = *errorp;
   if (error)
     {
+      g_debug ("Request caught error: %s", error->message);
+
       if (!pull_data->caught_error)
         {
           pull_data->caught_error = TRUE;