fix: --todos in parallel and feedback on process isolation

src/Plugins/ProcessIsolation.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest\Plugins;
+
+use Pest\Contracts\Plugins\HandlesArguments;
+use Pest\Exceptions\InvalidOption;
+
+/**
+ * @internal
+ */
+final class ProcessIsolation implements HandlesArguments
+{
+    use Concerns\HandleArguments;
+
+    /**
+     * {@inheritDoc}
+     */
+    public function handleArguments(array $arguments): array
+    {
+        if ($this->hasArgument('--process-isolation', $arguments)) {
+            throw new InvalidOption('The [--process-isolation] option is not supported.');
+        }
+
+        return $arguments;
+    }
+}