Update composer.json for PHP 7.2

vendor/guzzlehttp/guzzle/src/BodySummarizer.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace GuzzleHttp;
+
+use Psr\Http\Message\MessageInterface;
+
+final class BodySummarizer implements BodySummarizerInterface
+{
+    /**
+     * @var int|null
+     */
+    private $truncateAt;
+
+    public function __construct(int $truncateAt = null)
+    {
+        $this->truncateAt = $truncateAt;
+    }
+
+    /**
+     * Returns a summarized message body.
+     */
+    public function summarize(MessageInterface $message): ?string
+    {
+        return $this->truncateAt === null
+            ? \GuzzleHttp\Psr7\Message::bodySummary($message)
+            : \GuzzleHttp\Psr7\Message::bodySummary($message, $this->truncateAt);
+    }
+}