ca69d0f571
This will help mitigating any discrepancies between the issuer configured and the one returned by the OIDC provider. This also removes the need for configuring the `account_management_url` explicitely, as it will now be loaded from the OIDC discovery, as per MSC2965. Because we may now fetch stuff for the .well-known/matrix/client endpoint, this also transforms the client well-known resource to be asynchronous.