title: Two fields overwriting each others values on saving in Backpack for Laravel CRUD (spatie/laravel-tags implementation issues)?
body: <p>I am trying to use spatie/laravel-tags together with Backpack for Laravel. I have 2 types of tags defined. Currently I have extended the Tag model from spatie/laravel-tags as MyCategory and MyTag and added global scopes to separate the two tag types. This works to the extent that it will display the current categories and tags correctly in Backpack, but when I try to save any changes it will only save the entries in the last field, and delete everything in the first field.</p>
  
  <p>Here is my current field configuration for my CRUD:</p>
  
  <pre><code>        $this-&gt;crud-&gt;addField([
              'name' =&gt; 'categories',
              'label' =&gt; 'Categories',
              'type' =&gt; 'select2_multiple',
              'tab' =&gt; 'Overview',
              'attribute' =&gt; 'name',
              'model' =&gt; 'App\MyCategory',
              'pivot' =&gt; true,
          ]);
  
          $this-&gt;crud-&gt;addField([
              'name' =&gt; 'tags',
              'label' =&gt; 'Tags',
              'type' =&gt; 'select2_multiple',
              'tab' =&gt; 'Overview',
              'attribute' =&gt; 'name',
              'model' =&gt; 'App\MyTag',
              'pivot' =&gt; true,
          ]);
  </code></pre>
  
  <p>When I check Laravel Telescope I see that the same thing happens for both fields. First all current tags (regardless of type) for the item I am saving are deleted, and the new tags from the field are added. This is then repeated for the second field, which of course deletes the tags from the first field that should also be kept.</p>
  
  <p>It seems that GlobalScope on my extended Tag models does not stick around for this part. Is there any way to reintroduce the scopes into the queries run by backpack to get these tags to save correctly?</p>