Remove unused strings

app/src/main/res/values-ru/strings.xml

@@ -241,5 +241,4 @@
     <string name="genres">Жанры</string>
     <string name="state_finished">Завершено</string>
     <string name="state_ongoing">Онгоинг</string>
-    <string name="state_unknown">Неизвестно</string>
 </resources>

app/src/main/res/values/strings.xml

@@ -242,5 +242,4 @@
     <string name="genres">Genres</string>
     <string name="state_finished">Finished</string>
     <string name="state_ongoing">Ongoing</string>
-    <string name="state_unknown">Unknown</string>
 </resources>