cities: fix Berlin translation to spanish

Author: ebarped

contributions/cities/DE.json

@@ -24295,7 +24295,7 @@
       "hr": "Berlin",
       "fa": "برلین",
       "de": "Berlin",
-      "es": "Berlina",
+      "es": "Berlín",
       "fr": "Berlin",
       "ja": "ベルリン",
       "it": "Berlino",
@@ -291263,4 +291263,4 @@
     "flag": 1,
     "wikiDataId": "Q630383"
   }
-]
+]