mod_http_oauth2: Fix inclusion of role in refreshed access tokens `refresh_token_info` does not carry the role, and due to behavior prior to prosody trunk rev a1ba503610ed it would have reverted to the users' default role. After that it instead issues a token without role which is thus not usable with e.g. mod_rest

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summary: Log a message once per minute
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This module sends `-- MARK --` to the log once per minute. This may be
useful to give a sense of how busy the server is or see that logging and
timers are still working.