[stable/zed] Change Loki log_level from info to warn (#1134)

This is an automated cherry-pick of #1126
/assign mnaser
diff --git a/roles/loki/vars/main.yml b/roles/loki/vars/main.yml
index fd17dac..dbefa79 100644
--- a/roles/loki/vars/main.yml
+++ b/roles/loki/vars/main.yml
@@ -14,6 +14,8 @@
 
 _loki_helm_values:
   loki:
+    server:
+      log_level: warn
     image:
       registry: "{{ atmosphere_images['loki'] | vexxhost.kubernetes.docker_image('domain') }}"
       repository: "{{ atmosphere_images['loki'] | vexxhost.kubernetes.docker_image('path') }}"