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/guzzlehttp/promises/src/TaskQueueInterface.php

@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GuzzleHttp\Promise;
+
+interface TaskQueueInterface
+{
+    /**
+     * Returns true if the queue is empty.
+     */
+    public function isEmpty(): bool;
+
+    /**
+     * Adds a task to the queue that will be executed the next time run is
+     * called.
+     */
+    public function add(callable $task): void;
+
+    /**
+     * Execute all of the pending task in the queue.
+     */
+    public function run(): void;
+}