SQSCANGHA-89 Fix possible command injection

It is unlikely to be a real concern, since an attacker having the possibility to edit a pipeline can easily execute any command, but at least our step won't be involved

test/assertFileExists

@@ -1,8 +1,10 @@
 #!/bin/bash
 
+set -eou pipefail
+
 error() { echo -e "\\e[31m✗ $*\\e[0m"; }
 
-if [ ! -f $1 ]; then
+if [ ! -f "$1" ]; then
   error "File '$1' not found"
   exit 1
 fi