Add Override annotations where appropriate

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/material/Banner.java

@@ -28,6 +28,7 @@ public class Banner extends MaterialData implements Attachable {
         return getItemType() == Material.LEGACY_WALL_BANNER;
     }
 
+    @Override
     public BlockFace getAttachedFace() {
         if (isWallBanner()) {
             byte data = getData();
@@ -52,6 +53,7 @@ public class Banner extends MaterialData implements Attachable {
         }
     }
 
+    @Override
     public BlockFace getFacing() {
         byte data = getData();
 
@@ -112,6 +114,7 @@ public class Banner extends MaterialData implements Attachable {
         }
     }
 
+    @Override
     public void setFacingDirection(BlockFace face) {
         byte data;