Support OpenID Connect authentication

[schuerg]

Are there plans to add OpenID Connect authentication support? With this feature existing OIDC identity providers such as keycloak, dex and social logins could be used.

Relates to #174

[Kovah]

Will probably be integrated together with other authentication methods like LDAP, if it's easy to implement.

[milindpatel63]

Just an idea.... Many people are using cloudflare tunnels for exposing selfhosting stuff... And cloudflare has cloudflare access for authentication....

Would be great to use cloudfare access to authenticate linkace...