FIX(umami): fix DISABLE_LOGIN env variable syntax

- Change env format from map to list style
- Use proper Kubernetes env var specification

umami/helm-values.yaml

@@ -28,7 +28,8 @@ envFrom:
 
 # Disable login (using Authelia for authentication)
 env:
-  DISABLE_LOGIN: "1"
+  - name: DISABLE_LOGIN
+    value: "1"
 
 ingress:
   enabled: false  # Will use our main ingress