* Use embedded version of Element Call: for in-app room calls, the app will use an embedded version of Element Call shipped with the app instead of using an external service.
* Remove `ElementCallBaseUrlProvider` so we don't use the Element well known file to get the base URL anymore
* Remove `ElementCallConfig.DEFAULT_BASE_URL` since it's not used anymore
* Restore the usage of the custom EC base URL in developer settings as the actual base URL, it present
* Add a way to customise the embedded EC analytic credentials
* Update CI to use the EC analytic credentials as secrets
* Improve the custom URL placeholder to include the `/room` suffix
e2febabcf6