Update OIDC response_type to use authorization code flow

This enables PKCE. The implicit flow is often deprecated bhy auth providers

Author: cgalibern

src/js/OidcConfiguration.js

@@ -2,7 +2,7 @@ const baseUrl = window.location.protocol + "//" + window.location.host
 const initData = {
 	client_id: "ringfs",
 	redirect_uri: baseUrl + "/authentication/callback",
-	response_type: "id_token token",
+	response_type: "code",
 	scope: "openid profile email offline_access opensvc:om2 opensvc:om2:root opensvc:om2:guest grant",
 	silent_redirect_uri: baseUrl + "/authentication/silent_callback",
 	automaticSilentRenew: true,