run test only on Linux

tests/runtime.bats

@@ -130,3 +130,7 @@ runInScriptConsole() {
   assert "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; style-src 'self' 'unsafe-inline';" get-csp-value
   assert 'Europe/Madrid' get-timezone-value
 }
+
+@test "[${SUT_DESCRIPTION}] ensure that 'ps' command is available" {
+  command -v ps # Check for binary presence in the current PATH
+}

tests/test_helpers.psm1

@@ -22,10 +22,6 @@ if(-Not (Test-CommandExists docker)) {
     Write-Error "docker is not available"
 }
 
-if(-Not (Test-CommandExists ps)) {
-    Write-Error "ps is not available"
-}
-
 function Retry-Command {
     [CmdletBinding()]
     param (