t / t4101 / diff.0-2on commit t/t5538-push-shallow.sh: avoid "test <cond> -a/-o <cond>" (754b574)
   1--- a/frotz
   2+++ b/frotz
   3@@ -1,2 +1,2 @@
   4 a
   5-b
   6+b
   7\ No newline at end of file