t/test-lib-functions.sh: avoid "test <cond> -a/-o <cond>"

diff --git a/RelNotes b/RelNotes
index 61c3b54134d985cef6071014604d5b0499712df5..bf760914010786c830233effc8b96ddacfb114fd 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes/1.8.5.txt
\ No newline at end of file
+Documentation/RelNotes/2.1.0.txt
\ No newline at end of file