OpenID endpoint file includes wrong url without https

Question

I would like to use OpenID together with Gerrit. All services are served via reverse proxy. When I access
https://subdomain.mycompany.net/openidserver/op

following XML is produced

<?xml version="1.0" encoding="UTF-8"?>
  <XRDS xmlns="xri://$xrds">
  <XRD xmlns="xri://$xrd*($v*2.0)">
<Service>
  <Type>http://specs.openid.net/auth/2.0/server</Type>
  <URI>http://subdomain.mycompany.net/openidserver/op</URI>
</Service>
</XRD>
</XRDS>

The correct openidserver url should be https and not http

 <?xml version="1.0" encoding="UTF-8"?>
  <XRDS xmlns="xri://$xrds">
  <XRD xmlns="xri://$xrd*($v*2.0)">
<Service>
  <Type>http://specs.openid.net/auth/2.0/server</Type>
  <URI>https://subdomain.mycompany.net/openidserver/op</URI>
</Service>
</XRD>
</XRDS>

As I know Gerrit use this information to perform the login. The base url in the openid server is already configurated to "https://subdomain.mycompany.net/openidserver/"

Is there any option to change the url which will be delivered by /openidserver/op? // Philipp