* Avoid Nextcloud "Current user is not logged in" (Statuscode 997)
The error message results from oauth2-proxy trying to pass the
access token via URL. Instead it needs to be sent via header,
thus the Nextcloud provider requires a fix similar to what #1502
did before for the keycloak provider.
* Implement EnrichSession() for Nextcloud provider
Parse nested JSON to transform relevant information (groups, id,
email) from the OAuth2 userinfo endpoint into session.
* Update CHANGELOG.md (add link to PR #1750)
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