fix(tests): add typing to format validator

Author: TorstenDittmann

tests/Database/Format.php

@@ -21,7 +21,7 @@ class Format extends Text
      *
      * @return string
      */
-    public function getDescription()
+    public function getDescription(): string
     {
         return 'Value must be a valid email address';
     }
@@ -34,7 +34,7 @@ public function getDescription()
      * @param  mixed $value
      * @return bool
      */
-    public function isValid($value)
+    public function isValid($value): bool
     {
         if (!\filter_var($value, FILTER_VALIDATE_EMAIL)) {
             return false;