Fix-up iconography in recipient bottom sheet.

app/src/main/res/drawable-night/ic_group_24.xml

@@ -1,4 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
-  <item android:drawable="@drawable/ic_group_solid_24" />
-</layer-list>

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

@@ -29,7 +29,7 @@
                 android:id="@+id/message"
                 style="@style/Signal.Widget.ImageView.ActionButton"
                 android:contentDescription="@string/ConversationSettingsFragment__message"
-                app:srcCompat="@drawable/ic_message_24" />
+                app:srcCompat="@drawable/ic_chat_message_24" />
 
             <TextView
                 android:id="@+id/message_label"