fix: fix FlatList viewabilityConfig prop type (#37299)

Summary:
FlatList `viewabilityConfig` prop seems  no need to be any type. So I replaced it with `ViewabilityConfig` from `VirtualizedList.d.ts`

## Changelog:

[GENERAL] [FIXED] - change FlatList `viewabilityConfig` prop type `any` to `ViewabilityConfig`

Pull Request resolved: https://github.com/facebook/react-native/pull/37299

Test Plan: Ran yarn test-typescript and yarn test-typescript-offline with no errors.

Reviewed By: jacdebug

Differential Revision: D45689033

Pulled By: cipolleschi

fbshipit-source-id: e7fd31c534c5f47321b36d0d764f466392ad897e

packages/react-native/Libraries/Lists/FlatList.d.ts

@@ -12,6 +12,7 @@ import type {
   ListRenderItem,
   ViewToken,
   VirtualizedListProps,
+  ViewabilityConfig,
 } from '@react-native/virtualized-lists';
 import type {ScrollViewComponent} from '../Components/ScrollView/ScrollView';
 import type {StyleProp} from '../StyleSheet/StyleSheet';
@@ -144,7 +145,7 @@ export interface FlatListProps<ItemT> extends VirtualizedListProps<ItemT> {
   /**
    * See `ViewabilityHelper` for flow type and further documentation.
    */
-  viewabilityConfig?: any | undefined;
+  viewabilityConfig?: ViewabilityConfig | undefined;
 
   /**
    * Note: may have bugs (missing content) in some circumstances - use at your own risk.