Added comments FieldCounterTest.php

core/modules/views/tests/src/Kernel/Handler/FieldCounterTest.php

@@ -133,6 +133,7 @@ public function testPager(): void {
     $this->assertEquals('3', $counter);
 
     $view->destroy();
+    // Invalidate cache to fix issue:3456341
     $view->storage->invalidateCaches();
 
     // Test using the counter start option.