use modern flat form styles with more icons (#4098)

src/Form/Extension/IconExtension.php

@@ -35,13 +35,10 @@ final class IconExtension extends AbstractTypeExtension
         $view->vars['icon'] = $options['icon'] ?? null;
     }
 
-    /**
-     * @param OptionsResolver $resolver
-     */
     public function configureOptions(OptionsResolver $resolver): void
     {
         $resolver->setDefined(['icon']);
-        $resolver->setAllowedTypes('icon', 'string');
+        $resolver->setAllowedTypes('icon', ['string', 'null']);
         $resolver->setDefault('icon', '');
     }
 }

src/Form/Type/DurationType.php

@@ -32,6 +32,7 @@ final class DurationType extends AbstractType
             'preset_minutes' => null,
             'toggle' => false,
             'max_hours' => 24,
+            'icon' => 'clock',
         ]);
     }
 

src/Form/Type/QuickEntryTimesheetType.php

@@ -32,6 +32,7 @@ final class QuickEntryTimesheetType extends AbstractType
             'attr' => [
                 'placeholder' => '0:00',
             ],
+            'icon' => null,
         ];
 
         $duration = $options['duration_minutes'];