removed bats warnings (#1592)

tests/lib/setup_file.sh

@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# this should have effect globally, for all tests
+# https://github.com/bats-core/bats-core/blob/master/docs/source/warnings/BW02.rst
+bats_require_minimum_version 1.5.0
+
 debug() {
     echo 'exec 1<&-; exec 2<&-; exec 1>&3; exec 2>&1'
 }