GITBOOK-111: Add undocumented API routes

Author: Samy Pessé

docs/gitbook-api/reference/spaces/publishing.md

@@ -11,3 +11,7 @@ You can publish a space using the update endpoint [documented here](./#update-a-
 {% swagger src="../../../.gitbook/assets/openapi.yml" path="/spaces/{spaceId}/publishing/auth" method="get" %}
 [openapi.yml](../../../.gitbook/assets/openapi.yml)
 {% endswagger %}
+
+{% swagger src="https://api.gitbook.com/openapi.yaml" path="/spaces/{spaceId}/publishing/auth" method="post" %}
+[https://api.gitbook.com/openapi.yaml](https://api.gitbook.com/openapi.yaml)
+{% endswagger %}