fix(precognition): correctly set file data for avatar (#10840)

* fix: set first file as avatar

* Update example

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Co-authored-by: Tim MacDonald <[email protected]>

Author: SantosVilanculos

precognition.md

@@ -330,7 +330,7 @@ If you are validating a subset of a form's inputs with Precognition, it can be u
     id="avatar"
     type="file"
     onChange={(e) => {
-        form.setData('avatar', e.target.value);
+        form.setData('avatar', e.target.files[0);
 
         form.forgetError('avatar');
     }}