authelia: Set imagePullPolicy: IfNotPresent

We don't want to pull public container images that already exist.  This
creates prevents pods from starting if there is any connectivity issue
with the upstream registry.

authelia/kustomization.yaml

@@ -37,6 +37,7 @@ patches:
         spec:
           containers:
           - name: authelia
+            imagePullPolicy: IfNotPresent
             env:
             - name: AUTHELIA_STORAGE_POSTGRES_TLS_CERTIFICATE_CHAIN_FILE
               value: /run/authelia/certs/postgresql/tls.crt