Search Admin: Add Publishing API token

This is now required by the app to run, but can be an arbitrary value in
development.

Author: csutter

projects/search-admin/docker-compose.yml

@@ -30,6 +30,7 @@ services:
       TEST_DATABASE_URL: "mysql2://root:root@mysql-8/search_admin_test"
       REDIS_URL: redis://search-admin-redis
       DISCOVERY_ENGINE_DEFAULT_COLLECTION_NAME: "projects/780375417592/locations/global/collections/default_collection"
+      PUBLISHING_API_BEARER_TOKEN: example
 
   search-admin-app: &search-admin-app
     <<: *search-admin-base
@@ -46,6 +47,7 @@ services:
       BINDING: 0.0.0.0
       PORT: 3000
       DISCOVERY_ENGINE_DEFAULT_COLLECTION_NAME: "projects/780375417592/locations/global/collections/default_collection"
+      PUBLISHING_API_BEARER_TOKEN: example
     expose:
       - "3000"
     command: bin/dev