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/translation/Test/ProviderTestCase.php

@@ -0,0 +1,82 @@
+<?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\Translation\Test;
+
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\Translation\Dumper\XliffFileDumper;
+use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\Provider\ProviderInterface;
+use Symfony\Component\Translation\TranslatorBagInterface;
+use Symfony\Contracts\HttpClient\HttpClientInterface;
+
+/**
+ * A test case to ease testing a translation provider.
+ *
+ * @author Mathieu Santostefano <msantostefano@protonmail.com>
+ */
+abstract class ProviderTestCase extends TestCase
+{
+    protected HttpClientInterface $client;
+    protected LoggerInterface|MockObject $logger;
+    protected string $defaultLocale;
+    protected LoaderInterface|MockObject $loader;
+    protected XliffFileDumper|MockObject $xliffFileDumper;
+    protected TranslatorBagInterface|MockObject $translatorBag;
+
+    abstract public static function createProvider(HttpClientInterface $client, LoaderInterface $loader, LoggerInterface $logger, string $defaultLocale, string $endpoint): ProviderInterface;
+
+    /**
+     * @return iterable<array{0: ProviderInterface, 1: string}>
+     */
+    abstract public static function toStringProvider(): iterable;
+
+    /**
+     * @dataProvider toStringProvider
+     */
+    public function testToString(ProviderInterface $provider, string $expected)
+    {
+        $this->assertSame($expected, (string) $provider);
+    }
+
+    protected function getClient(): MockHttpClient
+    {
+        return $this->client ??= new MockHttpClient();
+    }
+
+    protected function getLoader(): LoaderInterface
+    {
+        return $this->loader ??= $this->createMock(LoaderInterface::class);
+    }
+
+    protected function getLogger(): LoggerInterface
+    {
+        return $this->logger ??= $this->createMock(LoggerInterface::class);
+    }
+
+    protected function getDefaultLocale(): string
+    {
+        return $this->defaultLocale ??= 'en';
+    }
+
+    protected function getXliffFileDumper(): XliffFileDumper
+    {
+        return $this->xliffFileDumper ??= $this->createMock(XliffFileDumper::class);
+    }
+
+    protected function getTranslatorBag(): TranslatorBagInterface
+    {
+        return $this->translatorBag ??= $this->createMock(TranslatorBagInterface::class);
+    }
+}