Update cors and website settings for log upload

The method is required for CORS to work.

Change-Id: Ie4cce69623a1abb798ff57873980e76bf2d3fa8f
diff --git a/roles/upload-logs-gcs/library/zuul_google_storage_upload.py b/roles/upload-logs-gcs/library/zuul_google_storage_upload.py
index da9734a..f658113 100755
--- a/roles/upload-logs-gcs/library/zuul_google_storage_upload.py
+++ b/roles/upload-logs-gcs/library/zuul_google_storage_upload.py
@@ -627,8 +627,12 @@
         self.prefix = prefix or ''
 
         self.bucket = client.bucket(container)
-        cors = [{'origin': ['*']}]
+        cors = [
+            {'method': ['GET', 'HEAD']},
+            {'origin': ['*']}
+        ]
         self.bucket.cors = cors
+        self.bucket.website = {"mainPageSuffix": "index.html"}
         self.bucket.update()
 
         self.url = os.path.join('https://storage.googleapis.com/',