docs(Page): Fix missing import in page demos (#12685)

Author: wise-king-sullyman

packages/react-core/src/demos/Page.md

@@ -23,6 +23,11 @@ import swaggerIcon from '@patternfly/react-core/src/demos/assets/camel-swagger-j
 import azureIcon from '@patternfly/react-core/src/demos/assets/FuseConnector_Icons_AzureServices.png';
 import restIcon from '@patternfly/react-core/src/demos/assets/FuseConnector_Icons_REST.png';
 import { data } from '@patternfly/react-core/src/demos/CardView/examples/CardViewData.jsx';
+import RhUiSettingsFillIcon from '@patternfly/react-icons/dist/esm/icons/rh-ui-settings-fill-icon';
+import RhUiQuestionMarkCircleIcon from '@patternfly/react-icons/dist/esm/icons/rh-ui-question-mark-circle-icon';
+import RhUiQuestionMarkCircleFillIcon from '@patternfly/react-icons/dist/esm/icons/rh-ui-question-mark-circle-fill-icon';
+import pfLogo from '@patternfly/react-core/src/demos/assets/PF-HorizontalLogo-Color.svg';
+import imgAvatar from '@patternfly/react-core/src/components/assets/avatarImg.svg';
 
 - All examples set the `isManagedSidebar` prop on the Page component to have the sidebar automatically close for smaller screen widths. You can also manually control this behavior by not adding the `isManagedSidebar` prop and instead:
   1. Add an onNavToggle callback to PageHeader