Auth: Split signout_redirect_url into per provider settings (#75269)

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* Update docs/sources/setup-grafana/configure-security/configure-authentication/grafana/index.md

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* Split signout_redirect_url into per provider settings

* update docs

* update devenvs

* add missing struct tag

---------

Co-authored-by: Rao, B V Chalapathi <b_v_chalapathi.rao@nokia.com>
Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>
Co-authored-by: jguer <me@jguer.space>

devenv/docker/blocks/auth/jwt_proxy/docker-compose.yaml

@@ -1,5 +1,5 @@
   oauthkeycloakdb:
-    image: docker.io/library/postgres:12-alpine
+    image: docker.io/library/postgres:16-alpine
     container_name: oauthkeycloakdb
     environment:
       POSTGRES_DB: keycloak
@@ -10,7 +10,7 @@
     restart: unless-stopped
 
   oauthkeycloak:
-    image: quay.io/keycloak/keycloak:21.1
+    image: quay.io/keycloak/keycloak:23.0
     container_name: oauthkeycloak
     command: start-dev
     environment: