Fix bg color of WP landing screen on light theme

Author: ovitrif

WordPress/src/main/res/values/colors.xml

@@ -33,7 +33,7 @@
     <color name="login_prologue_background_circle_pink">@color/pink_10</color>
 
     <!-- Login Prologue Revamped -->
-    <color name="login_prologue_revamped_background">@color/white</color>
+    <color name="login_prologue_revamped_background">@color/gray_0</color>
     <color name="login_prologue_revamped_icon">@color/gray_80</color>
 
     <!-- Prepublishing Nudges -->