Build modified streamline images

The official image from streamline does not currently work for the arm64
platform. As a temporary measure, the source code and docker build scripts
have been lifted from the official images and are used to build locally.

Some additional modifications are made to reduce overall image size, these
are documented in docker/README.md

docker/streamline-src/vendor/symfony/css-selector/CssSelectorConverter.php

@@ -0,0 +1,67 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\CssSelector;
+
+use Symfony\Component\CssSelector\Parser\Shortcut\ClassParser;
+use Symfony\Component\CssSelector\Parser\Shortcut\ElementParser;
+use Symfony\Component\CssSelector\Parser\Shortcut\EmptyStringParser;
+use Symfony\Component\CssSelector\Parser\Shortcut\HashParser;
+use Symfony\Component\CssSelector\XPath\Extension\HtmlExtension;
+use Symfony\Component\CssSelector\XPath\Translator;
+
+/**
+ * CssSelectorConverter is the main entry point of the component and can convert CSS
+ * selectors to XPath expressions.
+ *
+ * @author Christophe Coevoet <stof@notk.org>
+ */
+class CssSelectorConverter
+{
+    private Translator $translator;
+    private array $cache;
+
+    private static array $xmlCache = [];
+    private static array $htmlCache = [];
+
+    /**
+     * @param bool $html Whether HTML support should be enabled. Disable it for XML documents
+     */
+    public function __construct(bool $html = true)
+    {
+        $this->translator = new Translator();
+
+        if ($html) {
+            $this->translator->registerExtension(new HtmlExtension($this->translator));
+            $this->cache = &self::$htmlCache;
+        } else {
+            $this->cache = &self::$xmlCache;
+        }
+
+        $this->translator
+            ->registerParserShortcut(new EmptyStringParser())
+            ->registerParserShortcut(new ElementParser())
+            ->registerParserShortcut(new ClassParser())
+            ->registerParserShortcut(new HashParser())
+        ;
+    }
+
+    /**
+     * Translates a CSS expression to its XPath equivalent.
+     *
+     * Optionally, a prefix can be added to the resulting XPath
+     * expression with the $prefix parameter.
+     */
+    public function toXPath(string $cssExpr, string $prefix = 'descendant-or-self::'): string
+    {
+        return $this->cache[$prefix][$cssExpr] ??= $this->translator->cssToXPath($cssExpr, $prefix);
+    }
+}