code style fix

add command tests

tests/Feature/SSHCommands/System/ReadFileCommandTest.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Tests\Feature\SSHCommands\System;
+
+use App\SSHCommands\System\ReadFileCommand;
+use Tests\TestCase;
+
+class ReadFileCommandTest extends TestCase
+{
+    public function test_generate_command()
+    {
+        $command = new ReadFileCommand('/path');
+
+        $expected = <<<'EOD'
+        cat /path;
+        EOD;
+
+        $this->assertStringContainsString($expected, $command->content());
+    }
+}