Fix: Switch the check for strauss.phar for better compatibility (#6688)

Author: borkweb

Diff for: composer.json

@@ -38,7 +38,7 @@
         "test": "./vendor/bin/phpunit --colors --stop-on-failure",
         "unreleased": "./vendor/bin/since-unreleased.sh",
         "strauss": [
-            "[[ -f ./bin/strauss.phar ]] || curl -o bin/strauss.phar -L -C - https://github.com/BrianHenryIE/strauss/releases/download/0.13.0/strauss.phar",
+            "test -f ./bin/strauss.phar || curl -o bin/strauss.phar -L -C - https://github.com/BrianHenryIE/strauss/releases/download/0.13.0/strauss.phar",
             "vendor/stellarwp/validation/bin/set-domain domain=give",
             "@php bin/strauss.phar"
         ],