Tabs styling improvements (#8366)

* fix(tabs): delay loadView when animation runs

* chore: update api.md

* chore: remove unnecessary casting

* test: Added disabled test for changing tabs

* tabs(ios): added tabs styling in ios

* tabs: added iosAlignment property

* tabs: textTransform support

* tabs: iosAlignment moved to tabstrip

* test: add frame-in-tabs test

* chore: addressing PR comments

* chore: addressing PR comments

* chore: call method on the instance instead of call

* chore: move IOSAlignment property

* chore: update comments

* fix: texttransform to tabstrip in bottomnavigation

* chore: add new item to native-api-usage

* chore: remove unneeded setNativeView call

* chore: removed unneeded check

Co-authored-by: Dimitar Topuzov <dtopuzov@gmail.com>

api-reports/NativeScript.api.md

@@ -1239,6 +1239,9 @@ export class iOSApplication {
     window: any /* UIWindow */;
 }
 
+// @public
+export type IOSTabBarItemsAlignment = "leading" | "justified" | "center" | "centerSelected";
+
 // @public
 export const isAndroid: boolean;
 
@@ -2274,6 +2277,8 @@ export class Tabs extends TabNavigationBase {
 
     ios: any /* UITabBarController */;
 
+    iOSTabBarItemsAlignment: IOSTabBarItemsAlignment;
+
     items: Array<TabContentItem>;
 
     offscreenTabLimit: number;