[ENH] - Transition from traefik-forward-auth to oauth2-proxy

[costrouc]

Feature description

Move our transparent authentication from traefik-forward-auth to oauth2-proxy.

Value and/or benefit

There are several issues with traefik-forward-auth:

• project health https://github.com/thomseddon/traefik-forward-auth hasn't seen a merge in around 6 months and has many PRs stuck for feature that we need
• does not support disabling tls verification (useful for development deployments where getting tls certifications is not possible)
• no way to get authorization token from oauth2/openid connect authentication

Oauth2-proxy should be a drop in replacement feature wise to clients.

Anything else?

No response

[trallard]

@costrouc is this still applicable/of interest?

[iameskild]

@trallard I believe this is something that we are interested in including. This is something that is being explored as part of the work being done for the CDS Dashboards replacement (see the JHub-Apps repo).

[dcmcand]

Related to #1024