OpenID generic provider support

[offtherailz]

Description

Provide a generic support for an openID Connect provider.

Acceptance criteria

• MapStore can be configured via mapstore-ovr.properies to be connected to a generic openid provider
• The configuration allows to configure standard minimal properties to allow the user to login, with optional user creation. The minimal are:
  • discoveryUrl : to properly
  • clientId
  • clientSecret
  • principalKey: to identify the claim to use for the username.
• The login should be available as an alternative login method in he login form or direct (as for keycloak, google etc..)
• Logout have to be impelmented too.

The purpose is to provide the support to allow login via oidc + LDAP, for services like Azure.

Other useful information

[offtherailz]

@ElenaGallo I'll test this and let you know

[offtherailz]

According with this
https://learn.microsoft.com/en-us/entra/identity-platform/scopes-oidc

We don't have the scopes "groups". For this reason @afabiani will provide an additional fix to support the request of the groups scope.

[afabiani]

@offtherailz patch provided here