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/vlucas/phpdotenv/src/Parser/Lines.php

@@ -0,0 +1,127 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Dotenv\Parser;
+
+use Dotenv\Util\Regex;
+use Dotenv\Util\Str;
+
+final class Lines
+{
+    /**
+     * This class is a singleton.
+     *
+     * @codeCoverageIgnore
+     *
+     * @return void
+     */
+    private function __construct()
+    {
+        //
+    }
+
+    /**
+     * Process the array of lines of environment variables.
+     *
+     * This will produce an array of raw entries, one per variable.
+     *
+     * @param string[] $lines
+     *
+     * @return string[]
+     */
+    public static function process(array $lines)
+    {
+        $output = [];
+        $multiline = false;
+        $multilineBuffer = [];
+
+        foreach ($lines as $line) {
+            [$multiline, $line, $multilineBuffer] = self::multilineProcess($multiline, $line, $multilineBuffer);
+
+            if (!$multiline && !self::isCommentOrWhitespace($line)) {
+                $output[] = $line;
+            }
+        }
+
+        return $output;
+    }
+
+    /**
+     * Used to make all multiline variable process.
+     *
+     * @param bool     $multiline
+     * @param string   $line
+     * @param string[] $buffer
+     *
+     * @return array{bool,string,string[]}
+     */
+    private static function multilineProcess(bool $multiline, string $line, array $buffer)
+    {
+        $startsOnCurrentLine = $multiline ? false : self::looksLikeMultilineStart($line);
+
+        // check if $line can be multiline variable
+        if ($startsOnCurrentLine) {
+            $multiline = true;
+        }
+
+        if ($multiline) {
+            \array_push($buffer, $line);
+
+            if (self::looksLikeMultilineStop($line, $startsOnCurrentLine)) {
+                $multiline = false;
+                $line = \implode("\n", $buffer);
+                $buffer = [];
+            }
+        }
+
+        return [$multiline, $line, $buffer];
+    }
+
+    /**
+     * Determine if the given line can be the start of a multiline variable.
+     *
+     * @param string $line
+     *
+     * @return bool
+     */
+    private static function looksLikeMultilineStart(string $line)
+    {
+        return Str::pos($line, '="')->map(static function () use ($line) {
+            return self::looksLikeMultilineStop($line, true) === false;
+        })->getOrElse(false);
+    }
+
+    /**
+     * Determine if the given line can be the start of a multiline variable.
+     *
+     * @param string $line
+     * @param bool   $started
+     *
+     * @return bool
+     */
+    private static function looksLikeMultilineStop(string $line, bool $started)
+    {
+        if ($line === '"') {
+            return true;
+        }
+
+        return Regex::occurrences('/(?=([^\\\\]"))/', \str_replace('\\\\', '', $line))->map(static function (int $count) use ($started) {
+            return $started ? $count > 1 : $count >= 1;
+        })->success()->getOrElse(false);
+    }
+
+    /**
+     * Determine if the line in the file is a comment or whitespace.
+     *
+     * @param string $line
+     *
+     * @return bool
+     */
+    private static function isCommentOrWhitespace(string $line)
+    {
+        $line = \trim($line);
+
+        return $line === '' || (isset($line[0]) && $line[0] === '#');
+    }
+}