Update external storage docs (#576)

docusaurus/video/docusaurus/docs/api/_common_/storage.mdx

@@ -220,6 +220,8 @@ The following policy needs to be attached to your queue (replace the value of Re
 To use Google Cloud Storage as your storage provider, you need to send your [service account](https://cloud.google.com/iam/docs/service-accounts-create) credentials as they are stored in your JSON file.
 Stream only needs permission to write new files, it is not necessary to grant any other permission.
 
+> **Note:**: Note: We recommend reading the credentials from the file to avoid issues with copying and pasting errors.
+
 <Tabs groupId="examples">
 <TabItem value="js" label="JavaScript">
 
@@ -238,12 +240,15 @@ await serverSideClient.createExternalStorage({
 <TabItem value="py" label="Python">
 
 ```py
+with open("/path/to/your/service-account-file.json") as service_account_file:
+    creds = service_account_file.read()
+
 client.create_external_storage(
     name='my-gcs',
     storage_type='gcs',
     bucket='my-bucket',
     path='directory_name/',
-    gcs_credentials="content of the service account file"
+    gcs_credentials=creds
 )
 ```
 </TabItem>