test/atomicity: redirect output from "which"

Without redirection, this produced some slightly confusing output in
case gdb was present.

diff --git a/test/atomicity b/test/atomicity
index f9dbc9a61413e30c72848849404421e7bc6be2ca..34642388430ff8c544017764c0d03222c69fa217 100755 (executable)
--- a/test/atomicity
+++ b/test/atomicity
@@ -7,7 +7,7 @@ test_description='atomicity'
 # final database contents should be the same regardless of when (or
 # if) it is killed and restarted.
 
-if which gdb; then
+if which gdb 1>/dev/null 2>&1; then
     test_set_prereq GDB
 
 # Create a maildir structure to also stress flag synchronization