title: how to upgrade laravel 6 to 7
body: <p>i am trying to upgrade laravel 6 to 7, i got an error.</p>
  
  <pre><code> our requirements could not be resolved to an installable set of
   packages.
  
     Problem 1
       - Conclusion: remove laravel/framework v6.0.3
       - Conclusion: don't install laravel/framework v6.0.3
       - laravel/ui 2.x-dev requires illuminate/console ^7.0 -&gt; satisfiable by illuminate/console[7.x-dev, v7.0.0],
   laravel/framework[7.x-dev].
       - laravel/ui v2.0.0 requires illuminate/console ^7.0 -&gt; satisfiable by illuminate/console[7.x-dev, v7.0.0],
   laravel/framework[7.x-dev].
       - Can only install one of: laravel/framework[7.x-dev, v6.0.3].
       - don't install illuminate/console 7.x-dev|don't install laravel/framework v6.0.3
       - don't install illuminate/console v7.0.0|don't install laravel/framework v6.0.3
       - Installation request for laravel/framework (locked at v6.0.3, required as ^6.0) -&gt; satisfiable by laravel/framework[v6.0.3].
       - Installation request for laravel/ui ^2.0 -&gt; satisfiable by laravel/ui[2.x-dev, v2.0.0].
  </code></pre>