Build serverless request to Knative proxy
Description
In order to finish &1920 (closed) we need to add support for proxying serverless requests to Knative through GitLab Pages.
We need to move https://gitlab.com/grzesiek/serverless-proxy-poc POC to GitLab Pages, and integrate this with the new API that is being worked on in GitLab Rails -> gitlab#195964 (closed)
This will allow us to finalize the effort of building Serverless Domain support into GitLab Pages.
Edited by Grzegorz Bizon