Preset/stolperstein: Remove memorial:addr field

The `prerequisiteTag` did work nicely. However, the `"type": "address"` only allows to set `addr:*` keys, so we cannot re used it as is. Removing it for now…

data/fields/memorial/addr_addr.json

@@ -1,14 +0,0 @@
-{
-    "type": "address",
-    "key": "memorial:addr",
-    "keys": [
-        "memorial:addr:city",
-        "memorial:addr:street",
-        "memorial:addr:postcode",
-        "memorial:addr:housenumber"
-    ],
-    "label": "Nearest Building Address",
-    "prerequisiteTag": {
-        "key": "memorial:addr:street"
-    }
-}

data/presets/historic/memorial/stolperstein-EU.json

@@ -6,8 +6,7 @@
         "wikidata"
     ],
     "moreFields": [
-        "memorial/addr_string",
-        "memorial/addr_addr",
+        "memorial/addr",
         "subject/wikidata",
         "image",
         "wikimedia_commons",