drop building field from horse riding features

closes #273

data/presets/leisure/horse_riding.json

@@ -4,8 +4,7 @@
         "name",
         "access_simple",
         "operator",
-        "address",
-        "building"
+        "address"
     ],
     "moreFields": [
         "email",

data/presets/leisure/pitch/equestrian.json

@@ -1,8 +1,7 @@
 {
     "icon": "maki-horse-riding",
     "fields": [
-        "{leisure/pitch}",
-        "building"
+        "{leisure/pitch}"
     ],
     "geometry": [
         "area",