Remove unused color resource

(cherry picked from commit ea226a169721e41f56279bf29a8241089cb01193)

app/src/main/res/color/abc_primary_text_material_dark.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<selector xmlns:android="http://schemas.android.com/apk/res/android">
-
-    <item android:state_enabled="false" android:color="@color/primary_text_disabled_material_dark" />
-    <item android:color="@color/primary_text_default_material_dark" />
-</selector>