title: laravel-image-optimizer conflicts with spatie/browsershot
body: <p>Trying to install laravel-image-optimizer plugin I got errors:</p>
  
  <pre><code>$ composer require spatie/laravel-image-optimizer
  Using version ^1.4 for spatie/laravel-image-optimizer
  ./composer.json has been updated
  Loading composer repositories with package information
  Updating dependencies (including require-dev)
  Your requirements could not be resolved to an installable set of packages.
  
    Problem 1
      - The requested package spatie/browsershot (locked at 3.30.0, required as ^3.31) is satisfiable by spatie/browsershot[3.30.0] but these conflict with your requirements or minimum-stability.
  
  
  Installation failed, reverting ./composer.json to its original content.
  </code></pre>
  
  <p>My composer.json :</p>
  
  <pre><code>{
      "name": "laravel/laravel",
      "description": "The Laravel Framework.",
      "keywords": ["framework", "laravel"],
      "license": "MIT",
      "type": "project",
      "require": {
          "php": "^7.1.3",
          "alaouy/youtube": "^2.2",
          "aloha/twilio": "^4.0",
          "arrilot/laravel-widgets": "^3.12",
          "beyondcode/laravel-websockets": "^1.0",
          "cviebrock/eloquent-sluggable": "^4.5",
          "davejamesmiller/laravel-breadcrumbs": "5.x",
          "doctrine/dbal": "^2.8",
          "elasticquent/elasticquent": "dev-master",
          "facebook/graph-sdk": "^5.7",
          "fideloper/proxy": "^4.0",
          "google/apiclient": "^2.2",
          "intervention/image": "^2.4",
          "itsgoingd/clockwork": "^3.0",
          "jrean/laravel-user-verification": "^7.0",
          "laravel/framework": "5.8.*",
          "laravel/socialite": "^3.2",
          "laravel/tinker": "^1.0",
          "laravelium/sitemap": "^3.1",
          "maatwebsite/excel": "^3.1",
          "mews/captcha": "^2.2",
          "mews/purifier": "^2.1",
          "proengsoft/laravel-jsvalidation": "&gt;2.2.0",
          "pusher/pusher-php-server": "~3.0",
          "s-ichikawa/laravel-sendgrid-driver": "~2.0",
          "snowfire/beautymail": "dev-master",
          "socialiteproviders/instagram": "^3.0",
          "spatie/browsershot": "^3.31",
          "spatie/laravel-activitylog": "^3.1",
          "spatie/laravel-backup": "^6.1",
          "spatie/laravel-feed": "^2.1",
          "spatie/laravel-newsletter": "^4.2",
          "spatie/laravel-tags": "^2.1",
          "spipu/html2pdf": "^5.2",
          "themsaid/laravel-mail-preview": "^2.0",
          "unisharp/laravel-filemanager": "^1.9",
          "wboyz/laravel-enum": "^0.2.1",
          "willvincent/feeds": "1.1.*",
          "yajra/laravel-datatables-oracle": "^9.0.0"
      },
      "require-dev": {
          "barryvdh/laravel-debugbar": "^3.1",
          "filp/whoops": "^2.0",
          "fzaninotto/faker": "^1.4",
          "mockery/mockery": "^1.0",
          "nunomaduro/collision": "^2.0",
          "orangehill/iseed": "^2.6",
          "phpunit/phpunit": "^7.0",
          "xethron/migrations-generator": "^2.0"
      },
      "autoload": {
          "classmap": [
              "database/seeds",
              "database/factories"
          ],
          "psr-4": {
              "App\\": "app/"
          }
      },
      "autoload-dev": {
          "psr-4": {
              "Tests\\": "tests/"
          }
      },
      "extra": {
          "laravel": {
              "dont-discover": [
              ]
          }
      },
      "scripts": {
          "post-root-package-install": [
              "@php -r \"file_exists('.env') || copy('.env.example', '.env');\""
          ],
          "post-create-project-cmd": [
              "@php artisan key:generate"
          ],
          "post-autoload-dump": [
              "Illuminate\\Foundation\\ComposerScripts::postAutoloadDump",
              "@php artisan package:discover"
          ],
  
  
          "post-update-cmd": [
              "php artisan vendor:publish --provider=\"Proengsoft\\JsValidation\\JsValidationServiceProvider\" --tag=public --force"
          ]
  
      },
      "config": {
          "preferred-install": "dist",
          "sort-packages": true,
          "optimize-autoloader": true
      },
      "minimum-stability": "dev",
      "prefer-stable": true
  }
  </code></pre>
  
  <p>As I see here <a href="https://github.com/spatie/browsershot/releases" rel="nofollow noreferrer">https://github.com/spatie/browsershot/releases</a>
  latest version of it is 3.31.0</p>
  
  <p>and it my composer.json I have</p>
  
  <pre><code>"spatie/browsershot": "^3.31",
  </code></pre>
  
  <p>is a latest version, just as on spatie/browsershot/releases page.</p>
  
  <p>Which steps have I to take  ?</p>
  
  <p>Thanks!</p>