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/guzzle/src/PrepareBodyMiddleware.php

@@ -0,0 +1,105 @@
+<?php
+
+namespace GuzzleHttp;
+
+use GuzzleHttp\Promise\PromiseInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Prepares requests that contain a body, adding the Content-Length,
+ * Content-Type, and Expect headers.
+ *
+ * @final
+ */
+class PrepareBodyMiddleware
+{
+    /**
+     * @var callable(RequestInterface, array): PromiseInterface
+     */
+    private $nextHandler;
+
+    /**
+     * @param callable(RequestInterface, array): PromiseInterface $nextHandler Next handler to invoke.
+     */
+    public function __construct(callable $nextHandler)
+    {
+        $this->nextHandler = $nextHandler;
+    }
+
+    public function __invoke(RequestInterface $request, array $options): PromiseInterface
+    {
+        $fn = $this->nextHandler;
+
+        // Don't do anything if the request has no body.
+        if ($request->getBody()->getSize() === 0) {
+            return $fn($request, $options);
+        }
+
+        $modify = [];
+
+        // Add a default content-type if possible.
+        if (!$request->hasHeader('Content-Type')) {
+            if ($uri = $request->getBody()->getMetadata('uri')) {
+                if (is_string($uri) && $type = Psr7\MimeType::fromFilename($uri)) {
+                    $modify['set_headers']['Content-Type'] = $type;
+                }
+            }
+        }
+
+        // Add a default content-length or transfer-encoding header.
+        if (!$request->hasHeader('Content-Length')
+            && !$request->hasHeader('Transfer-Encoding')
+        ) {
+            $size = $request->getBody()->getSize();
+            if ($size !== null) {
+                $modify['set_headers']['Content-Length'] = $size;
+            } else {
+                $modify['set_headers']['Transfer-Encoding'] = 'chunked';
+            }
+        }
+
+        // Add the expect header if needed.
+        $this->addExpectHeader($request, $options, $modify);
+
+        return $fn(Psr7\Utils::modifyRequest($request, $modify), $options);
+    }
+
+    /**
+     * Add expect header
+     */
+    private function addExpectHeader(RequestInterface $request, array $options, array &$modify): void
+    {
+        // Determine if the Expect header should be used
+        if ($request->hasHeader('Expect')) {
+            return;
+        }
+
+        $expect = $options['expect'] ?? null;
+
+        // Return if disabled or if you're not using HTTP/1.1 or HTTP/2.0
+        if ($expect === false || $request->getProtocolVersion() < 1.1) {
+            return;
+        }
+
+        // The expect header is unconditionally enabled
+        if ($expect === true) {
+            $modify['set_headers']['Expect'] = '100-Continue';
+
+            return;
+        }
+
+        // By default, send the expect header when the payload is > 1mb
+        if ($expect === null) {
+            $expect = 1048576;
+        }
+
+        // Always add if the body cannot be rewound, the size cannot be
+        // determined, or the size is greater than the cutoff threshold
+        $body = $request->getBody();
+        $size = $body->getSize();
+
+        if ($size === null || $size >= (int) $expect || !$body->isSeekable()) {
+            $modify['set_headers']['Expect'] = '100-Continue';
+        }
+    }
+}