Removing deprecated flatMap

Author: Nixsm

Sources/ButtonBarPagerTabStripViewController.swift

@@ -259,11 +259,11 @@ open class ButtonBarPagerTabStripViewController: PagerTabStripViewController, Pa
 
         if reload {
             let indexPathsToReload = cells.enumerated()
-                .flatMap { (arg) -> IndexPath? in
+                .compactMap { (arg) -> IndexPath? in
                     let (index, cell) = arg
                     return cell == nil ? indexPaths[index] : nil
                 }
-                .flatMap { (indexPath: IndexPath) -> IndexPath? in
+                .compactMap { (indexPath: IndexPath) -> IndexPath? in
                     return (indexPath.item >= 0 && indexPath.item < buttonBarView.numberOfItems(inSection: indexPath.section)) ? indexPath : nil
                 }