Catch empty string.

app/Api/V1/Controllers/Search/AccountController.php

@@ -70,8 +70,8 @@ class AccountController extends Controller
     {
         Log::debug('Now in account search()');
         $manager = $this->getManager();
-        $query   = $request->get('query');
-        $field   = $request->get('field');
+        $query   = trim((string)$request->get('query'));
+        $field   = trim((string)$request->get('field'));
         $type    = $request->get('type') ?? 'all';
         if ('' === $query || !in_array($field, $this->validFields, true)) {
             return response(null, 422);