Expose a generic OpenID Connect authentication provider
Octopus Server already has a lot of oAuth/OpenID integrations built in (AzureAD, Okta, Google Apps etc) but all of them are provider-specific. It would be great to have a generic authentication provider for third-party identity servers (such as Keycloak) to expand on this even further. Considering all of the current implementations are already based on a common class (https://github.com/OctopusDeploy/OpenIDConnectAuthenticationProviders) I imagine this shouldn't require much work. Although generic provider could expose more customization on how to extract user information from ID token, for example. We are using AzureAD integration to cover this for now (Keycloak integration) and it works, but this looks more like a hacky workaround then a proper solution.