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/psr7/src/Header.php

@@ -0,0 +1,134 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GuzzleHttp\Psr7;
+
+final class Header
+{
+    /**
+     * Parse an array of header values containing ";" separated data into an
+     * array of associative arrays representing the header key value pair data
+     * of the header. When a parameter does not contain a value, but just
+     * contains a key, this function will inject a key with a '' string value.
+     *
+     * @param string|array $header Header to parse into components.
+     */
+    public static function parse($header): array
+    {
+        static $trimmed = "\"'  \n\t\r";
+        $params = $matches = [];
+
+        foreach ((array) $header as $value) {
+            foreach (self::splitList($value) as $val) {
+                $part = [];
+                foreach (preg_split('/;(?=([^"]*"[^"]*")*[^"]*$)/', $val) ?: [] as $kvp) {
+                    if (preg_match_all('/<[^>]+>|[^=]+/', $kvp, $matches)) {
+                        $m = $matches[0];
+                        if (isset($m[1])) {
+                            $part[trim($m[0], $trimmed)] = trim($m[1], $trimmed);
+                        } else {
+                            $part[] = trim($m[0], $trimmed);
+                        }
+                    }
+                }
+                if ($part) {
+                    $params[] = $part;
+                }
+            }
+        }
+
+        return $params;
+    }
+
+    /**
+     * Converts an array of header values that may contain comma separated
+     * headers into an array of headers with no comma separated values.
+     *
+     * @param string|array $header Header to normalize.
+     *
+     * @deprecated Use self::splitList() instead.
+     */
+    public static function normalize($header): array
+    {
+        $result = [];
+        foreach ((array) $header as $value) {
+            foreach (self::splitList($value) as $parsed) {
+                $result[] = $parsed;
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * Splits a HTTP header defined to contain a comma-separated list into
+     * each individual value. Empty values will be removed.
+     *
+     * Example headers include 'accept', 'cache-control' and 'if-none-match'.
+     *
+     * This method must not be used to parse headers that are not defined as
+     * a list, such as 'user-agent' or 'set-cookie'.
+     *
+     * @param string|string[] $values Header value as returned by MessageInterface::getHeader()
+     *
+     * @return string[]
+     */
+    public static function splitList($values): array
+    {
+        if (!\is_array($values)) {
+            $values = [$values];
+        }
+
+        $result = [];
+        foreach ($values as $value) {
+            if (!\is_string($value)) {
+                throw new \TypeError('$header must either be a string or an array containing strings.');
+            }
+
+            $v = '';
+            $isQuoted = false;
+            $isEscaped = false;
+            for ($i = 0, $max = \strlen($value); $i < $max; ++$i) {
+                if ($isEscaped) {
+                    $v .= $value[$i];
+                    $isEscaped = false;
+
+                    continue;
+                }
+
+                if (!$isQuoted && $value[$i] === ',') {
+                    $v = \trim($v);
+                    if ($v !== '') {
+                        $result[] = $v;
+                    }
+
+                    $v = '';
+                    continue;
+                }
+
+                if ($isQuoted && $value[$i] === '\\') {
+                    $isEscaped = true;
+                    $v .= $value[$i];
+
+                    continue;
+                }
+                if ($value[$i] === '"') {
+                    $isQuoted = !$isQuoted;
+                    $v .= $value[$i];
+
+                    continue;
+                }
+
+                $v .= $value[$i];
+            }
+
+            $v = \trim($v);
+            if ($v !== '') {
+                $result[] = $v;
+            }
+        }
+
+        return $result;
+    }
+}