chore(deps): update ghcr.io/authelia/authelia docker tag to v4.39.18

Author: renovate[bot]

k8s/infra/auth/authelia/values.yaml

@@ -2,7 +2,7 @@
 image:
   registry: ghcr.io
   repository: authelia/authelia
-  tag: 4.39.16 # renovate: docker=ghcr.io/authelia/authelia
+  tag: 4.39.18 # renovate: docker=ghcr.io/authelia/authelia
   pullPolicy: IfNotPresent
 
 certificates: