Update composer.json for PHP 7.2

vendor/psr/http-client/src/NetworkExceptionInterface.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Psr\Http\Client;
+
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Thrown when the request cannot be completed because of network issues.
+ *
+ * There is no response object as this exception is thrown when no response has been received.
+ *
+ * Example: the target host name can not be resolved or the connection failed.
+ */
+interface NetworkExceptionInterface extends ClientExceptionInterface
+{
+    /**
+     * Returns the request.
+     *
+     * The request object MAY be a different object from the one passed to ClientInterface::sendRequest()
+     *
+     * @return RequestInterface
+     */
+    public function getRequest(): RequestInterface;
+}