Add support for oidc

[Jeidnx]

requires TeamPiped/Piped-Backend#628

closes #463

[winston0410]

Hi, I wonder what is blocking this PR from being merged into main? Having OIDC for SSO is really valueable

[Jeidnx]

@winston0410 The backend part of this PR is not finished. Because i don't have a use case for this anymore, i stopped working on it a while ago. If anyone wants to have a go the biggest thing missing is the "database stuff", other than that i think the code just needs a once-over and it could be merged. I'd be happy to answer any questions or review some code for this

[Akruidenberg]

Is there anything need for this to merge. Would love to get this!

[Jeidnx]

@Akruidenberg I had some spare time and worked on this some time ago. As far as i am concerned this is good to go. I have been running an instance from this branch for 1-2 Months and haven't had any issues (yet). If anyone wants to try running this, there is also a branch of libretube which supports login via OIDC here.

On the backend side someone still needs to review the code before it can be merged.