update dockerfiles based on latest streamline image

The latest images incorporate all changes previously added by the dockerfiles.
The arm image however is still missing/unreliable from the registry and must be
built independently.

docker/streamline-src/vendor/sebastian/code-unit/src/TraitUnit.php

@@ -0,0 +1,24 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of sebastian/code-unit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\CodeUnit;
+
+/**
+ * @psalm-immutable
+ */
+final class TraitUnit extends CodeUnit
+{
+    /**
+     * @psalm-assert-if-true TraitUnit $this
+     */
+    public function isTrait(): bool
+    {
+        return true;
+    }
+}