I think there is a known problem with using this:
The Reporting plugin uses the server.host name to open a page to Kibana, which requires authentication. The Chromium browser has been found to change the address from http://0:5601 to http://0.0.0.0:5601 which causes the Reporting plugin to prevent sending the authentication headers, and the timeout therefore is happening while waiting on the Login page.
You can confirm this by looking at the URLs that get requested in the verbose logs of the Kibana server - (sorry but the pastebin link is not working right now)
The recommendation is to change server.host to 0.0.0.0 not simply "0". BTW no quotes are needed for this setting in the kibana.yml.
There is also a xpack.reporting.kibanaServer.hostname setting that will override the default setting: Reporting settings in Kibana | Kibana Guide [8.11] | Elastic -- but in this case it should be fine to just change the server.host to a value that Reporting can use.