title: Missing ["connectionName"] in new TableObject [CakePHP 3.x]
body: <p>I created a new Table per Migration for my project to enable AutoLogin per Cookie. 
  My problem is, that the TableObject is missing it's ["connectionName"] property on initialize. </p>
  
  <p>I tried to find a way to fix this, but the only way I found was setting the Connection with the ConnectionManager. This will work for now, but I'd really like to know where I made a mistake, and why the connectionName isn't set to 'default' on its own. </p>
  
  <p>My Migrationfile looks like this: </p>
  
  <pre><code>public function change()
  {
    $table = $this-&gt;table('autologins', ['id' =&gt; false, 'primary_key' =&gt; 'id']);
  
    $table-&gt;addColumn('id', 'uuid', [
      'limit' =&gt; 36,
      'null' =&gt; false,
    ]);
    $table-&gt;addColumn('token', 'string',[
      'null' =&gt; false,
      'limit' =&gt; 32,
    ]);
    $table-&gt;addColumn('user_agent', 'string',[
      'null' =&gt; false,
      'limit' =&gt; MysqlAdapter::TEXT_TINY,
    ]);
    $table-&gt;addColumn('user_id', 'uuid',[
      'limit' =&gt; 36,
      'null' =&gt; false,
    ]);
    $table-&gt;addColumn('expiry_date', 'datetime',[
      'null' =&gt; false,
    ]);
  
    $table-&gt;create();
  }
  </code></pre>
  
  <p>Without setting the Connection </p>
  
  <pre><code>$this-&gt;setConnection(ConnectionManager::get('default'));
  </code></pre>
  
  <p>I get the following var_dump:</p>
  
  <pre><code>object(App\Model\Table\AutologinsTable)#486 (8) { 
  ["registryAlias"]=&gt; string(10) "Autologins" 
  ["table"]=&gt; string(10) "autologins" 
  ["alias"]=&gt; string(10) "Autologins" 
  ["entityClass"]=&gt; string(26) "App\Model\Entity\Autologin" 
  ["associations"]=&gt; array(0) { } 
  ["behaviors"]=&gt; array(0) { } 
  ["defaultConnection"]=&gt; string(7) "default" 
  ["connectionName"]=&gt; NULL }
  </code></pre>