(chore): bump up composer

composer.lock

@@ -4,7 +4,7 @@
  "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
  "This file is @generated automatically"
  ],
- "content-hash": "f342e1279b408d73f9f41a414c74de73",
+ "content-hash": "5b6bc7de604342e4386f91ba14c121ad",
  "packages": [
  {
  "name": "Minds/Surge",
@@ -2570,28 +2570,29 @@
  },
  {
  "name": "stripe/stripe-php",
- "version": "v4.13.0",
+ "version": "v6.40.0",
  "source": {
  "type": "git",
  "url": "https://github.com/stripe/stripe-php.git",
- "reference": "834681b9cdfa68d88a27e36ec9e356b598a5f0e6"
+ "reference": "9c22ffab790ef4dae0f371929de50e8b53c9ec8d"
  },
  "dist": {
  "type": "zip",
- "url": "https://api.github.com/repos/stripe/stripe-php/zipball/834681b9cdfa68d88a27e36ec9e356b598a5f0e6",
- "reference": "834681b9cdfa68d88a27e36ec9e356b598a5f0e6",
+ "url": "https://api.github.com/repos/stripe/stripe-php/zipball/9c22ffab790ef4dae0f371929de50e8b53c9ec8d",
+ "reference": "9c22ffab790ef4dae0f371929de50e8b53c9ec8d",
  "shasum": ""
  },
  "require": {
  "ext-curl": "*",
  "ext-json": "*",
  "ext-mbstring": "*",
- "php": ">=5.3.3"
+ "php": ">=5.4.0"
  },
  "require-dev": {
+ "php-coveralls/php-coveralls": "1.*",
  "phpunit/phpunit": "~4.0",
- "satooshi/php-coveralls": "~0.6.1",
- "squizlabs/php_codesniffer": "~2.0"
+ "squizlabs/php_codesniffer": "~2.0",
+ "symfony/process": "~2.8"
  },
  "type": "library",
  "extra": {
@@ -2621,7 +2622,7 @@
  "payment processing",
  "stripe"
  ],
- "time": "2017-06-20T01:39:06+00:00"
+ "time": "2019-06-27T23:24:51+00:00"
  },
  {
  "name": "symfony/config",