To center the text of the header title

Bug: 261162446
Test: Manual test
Change-Id: Iae34d44aee1a6d55ba9dedef19c286fa65c27e26

res/layout/advanced_bt_entity_header.xml

@@ -21,6 +21,8 @@
     style="@style/EntityHeader"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
+    android:paddingStart="?android:attr/listPreferredItemPaddingStart"
+    android:paddingEnd="?android:attr/listPreferredItemPaddingEnd"
     android:orientation="vertical">
 
     <TextView
@@ -29,6 +31,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="center_horizontal"
+        android:gravity="center"
         android:ellipsize="marquee"
         android:textDirection="locale"/>
 

res/layout/bluetooth_broadcast_entity_header.xml

@@ -31,6 +31,7 @@
         style="@style/TextAppearance.EntityHeaderTitle"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:gravity="center"
         android:ellipsize="marquee"
         android:textDirection="locale"/>
 

res/layout/le_audio_bt_entity_header.xml

@@ -33,6 +33,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_gravity="center_horizontal"
+        android:gravity="center"
         android:ellipsize="marquee"
         android:textDirection="locale"/>