Spacing adjustments in reader settings sheet

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

@@ -15,7 +15,6 @@
             android:id="@+id/custom_brightness"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:layout_marginTop="16dp"
             android:paddingStart="16dp"
             android:paddingEnd="16dp"
             android:text="@string/pref_custom_brightness"

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

@@ -10,6 +10,7 @@
         android:id="@+id/pager_prefs"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
+        android:layout_marginBottom="8dp"
         android:paddingStart="16dp"
         android:paddingEnd="16dp"
         android:text="@string/pager_viewer"

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

@@ -15,6 +15,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginTop="16dp"
+            android:layout_marginBottom="8dp"
             android:paddingStart="16dp"
             android:paddingEnd="16dp"
             android:text="@string/pref_category_for_this_series"

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

@@ -12,6 +12,7 @@
         android:layout_height="wrap_content"
         android:paddingStart="16dp"
         android:paddingEnd="16dp"
+        android:layout_marginBottom="8dp"
         android:text="@string/webtoon_viewer"
         android:textAppearance="@style/TextAppearance.Tachiyomi.SectionHeader" />