optimize preview alignment

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

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

@@ -39,6 +39,7 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:contentDescription="@null"
+        android:scaleType="fitStart"
         android:visibility="invisible" />
 
     <com.google.android.material.button.MaterialButton