Revert "keycloak: temporarily disable keycloak-metrics-spi"

This reverts commit 903129d4

With the release of keycloak-metrics-spi 3.0.0 they added support
for Keycloak > 21.x [1]

[1]: https://github.com/aerogear/keycloak-metrics-spi/pull/157



Resolve: #499

Signed-off-by: Leonidas Spyropoulos <artafinde@archlinux.org>

roles/keycloak/tasks/main.yml

 - name: Install keycloak
-  pacman: name=jre11-openjdk,keycloak,keycloak-archlinux-theme,python-passlib state=present
+  pacman: name=jre11-openjdk,keycloak,keycloak-archlinux-theme,keycloak-metrics-spi,python-passlib state=present
 
 - name: Create postgres keycloak user
   postgresql_user: name="{{ vault_keycloak_db_user }}" password="{{ vault_keycloak_db_password }}"

tf-stage2/keycloak.tf

@@ -201,7 +201,8 @@ resource "keycloak_realm_events" "realm_events" {
   ]
 
   events_listeners = [
-    "jboss-logging", # keycloak enables the 'jboss-logging' event listener by default.
+    "jboss-logging",    # keycloak enables the 'jboss-logging' event listener by default.
+    "metrics-listener", # enable the prometheus exporter (keycloak-metrics-spi)
   ]
 }