Add PARKING_LOGGING_INTERVAL_MS as an environment variable

.env.example

@@ -7,3 +7,5 @@ APNS_BUNDLE_ID=
 
 # base64-encoded APNs private key
 APNS_PRIVATE_KEY=
+
+PARKING_LOGGING_INTERVAL_MS=

docker-compose.yml

@@ -10,6 +10,7 @@ x-common-environment: &common-server-environment
   APNS_TEAM_ID: ${APNS_TEAM_ID}
   APNS_KEY_ID: ${APNS_KEY_ID}
   APNS_PRIVATE_KEY: ${APNS_PRIVATE_KEY}
+  PARKING_LOGGING_INTERVAL_MS: ${PARKING_LOGGING_INTERVAL_MS}
   REDIS_URL: redis://redis:6379
 
 services: