Keycloak not reading 'kc_idp_hint' query param in an spring boot app when using keycloak 18 as a broker

I am using following configuration in app properties files in order to redirect to the Auth0 idp login page rather then keycloak login page :

Above conf is not working , ideally i think it should work .
Entire source is present here Github source code

Is there anything i am missing ? Can someone please help .

@dasniko @thomasdarimont can you please help on this ?

I tried the code as mentioned in comments at issue here [KEYCLOAK-14776] Allow to specify idpHint in Java based applications - Red Hat Issue Tracker
but it didnt work for me . Also i am using springbootproperties for keycloak than using keycloak.json .