feat: make PROXY_ROLE_ASSIGNMENT_DRIVER configurable

   Allow PROXY_ROLE_ASSIGNMENT_DRIVER to be set via environment variable
   in .env file, with oidc remaining as the default value. I was frustrated that this was hard coded since my OIDC doesn't offer the complete scope, so I made it configurable.

Author: maybenotconnor

.env.example

@@ -298,6 +298,9 @@ LDAP_BIND_PASSWORD=
 
 ## Autoprovisioning Mode ##
 # Use together with idm/external-idp.yml
+# Role assignment driver for the proxy. Defaults to "oidc".
+# Possible values: "oidc", "default"
+PROXY_ROLE_ASSIGNMENT_DRIVER=
 # If you want to use a keycloak for local testing, you can use testing/external-keycloak.yml and testing/ldap-manager.yml
 # Domain of your Identity Provider.
 IDP_DOMAIN=

idm/external-idp.yml

@@ -15,7 +15,7 @@ services:
       FRONTEND_READONLY_USER_ATTRIBUTES: "user.onPremisesSamAccountName,user.displayName,user.mail,user.passwordProfile,user.accountEnabled,user.appRoleAssignments"
       PROXY_OIDC_REWRITE_WELLKNOWN: "true"
       WEB_OIDC_CLIENT_ID: ${OC_OIDC_CLIENT_ID:-web}
-      PROXY_ROLE_ASSIGNMENT_DRIVER: "oidc"
+      PROXY_ROLE_ASSIGNMENT_DRIVER: ${PROXY_ROLE_ASSIGNMENT_DRIVER:-oidc}
       OC_OIDC_ISSUER: ${IDP_ISSUER_URL:-https://keycloak.opencloud.test/realms/openCloud}
       # This specifies to start all services except idm and idp. These are replaced by external services.
       OC_EXCLUDE_RUN_SERVICES: idm,idp