add did resolver address to policy service configuration

docker-compose.yml

@@ -48,7 +48,7 @@ services:
     ports:
       - "9090:8080"
 
-  didresolver-driver-did-key:
+  driver-did-key:
     image: universalresolver/driver-did-key:latest
     ports:
       - "9091:8080"

env/policy.env

@@ -10,3 +10,4 @@ MONGO_PASS="root"
 MONGO_DBNAME="policy"
 MONGO_COLLECTION="policies"
 CACHE_ADDR="http://cache:8080"
+DID_RESOLVER_ADDR="http://didresolver:8080"