chore(deps): update dependency google/cloud-service-directory to ^0.4.0 (GoogleCloudPlatform#1279)

Author: renovate-bot

servicedirectory/composer.json

@@ -1,5 +1,5 @@
 {
     "require": {
-        "google/cloud-service-directory": "^0.3.0"
+        "google/cloud-service-directory": "^0.4.0"
     }
 }