owncloudcmd with Open ID Connect

[dragotin]

Pre-submission Checks

• [X] I checked for similar issues, but could not find any. I also checked the closed issues. I could not contribute additional information to any existing issue.
• [X] I will take the time to fill in all the required fields. I know that the bug report may be dismissed otherwise due to lack of information.

Feature description

owncloudcmd should be able to authenticate via OpenID Connect to run with oCIS.

Proposed solution

Use the existing code in the client to re-use that with the commandline client.

Alternative solutions you considered

It was considered to use the oidc-agent that works with for example rclone - but since we have the code already in the client it seems easier and more convenient to use that in owncloudcmd as well.

Additional context

No response