title: Laravel-Excel returns required error with all rows
body: <p>I am implementing <a href="https://github.com/Maatwebsite/Laravel-Excel" rel="nofollow noreferrer">Laravel-Excel</a> into my project and could not figure out the validation.</p>
  
  <p>I try to upload the <code>xlsx</code> file with one row of data in it but still, the import throws <code>required</code> error.</p>
  
  <p>Following is my <code>EventResultImport</code> code</p>
  
  <pre><code>namespace App\Imports;
  
  use App\Models\Data\EventResult;
  use Maatwebsite\Excel\Concerns\Importable;
  use Maatwebsite\Excel\Concerns\ToModel;
  use Maatwebsite\Excel\Concerns\WithHeadingRow;
  use Maatwebsite\Excel\Concerns\WithValidation;
  use Maatwebsite\Excel\Imports\HeadingRowFormatter;
  
  class EventResultImport implements ToModel, WithValidation, WithHeadingRow
  {
      use Importable;
  
      public function model(array $row)
      {
          HeadingRowFormatter::default('none');
  
          return new EventResult([
              'event_id' =&gt; $row[0],
              'event_name' =&gt; $row[1],
          ]);
      }
  
      public function rules(): array
      {
          return [
              //'EventId' =&gt; 'required|numeric', Tried this
              //'*.EventId' =&gt; 'required|numeric', Tried this
              '0' =&gt; 'required|numeric'
  
          ];
      }
  }
  </code></pre>
  
  <p>I get error on second-row event if there is numeric data in column <code>EventId</code>. </p>
  
  <p><a href="https://i.stack.imgur.com/DcoIp.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DcoIp.png" alt="enter image description here"></a></p>
  
  <p>Thank you</p>