Small UI tweaks.

- Update distance below avatar in conversation settings.
- Slightly increase bubble corner radius.

app/src/main/res/layout/conversation_settings_bio_preference_item.xml

@@ -10,7 +10,7 @@
         android:layout_width="0dp"
         android:layout_height="wrap_content"
         android:layout_marginStart="32dp"
-        android:layout_marginTop="12dp"
+        android:layout_marginTop="4dp"
         android:layout_marginEnd="32dp"
         android:gravity="center"
         android:textAppearance="@style/Signal.Text.Headline.Medium"

app/src/main/res/values/dimens.xml

@@ -30,7 +30,7 @@
 
     <dimen name="camera_contacts_horizontal_margin">16dp</dimen>
 
-    <dimen name="message_corner_radius">16dp</dimen>
+    <dimen name="message_corner_radius">18dp</dimen>
     <dimen name="message_corner_collapse_radius">4dp</dimen>
     <dimen name="message_bubble_corner_radius">2dp</dimen>
     <dimen name="message_bubble_shadow_distance">1.5dp</dimen>