Remove binary_sensor from domains.

We no longer use a binary_sensor. Also, the trailing comma was causing
validation failure (even though HACS itself is OK with it).

hacs.json

@@ -4,8 +4,7 @@
   "domains": [
     "climate",
     "light",
-    "lock",
-    "binary_sensor",  
+    "lock"
   ],
   "country": [
     "NZ",