Update ghcr.io/paperless-ngx/paperless-ngx Docker tag to v2.18.4

Author: renovate-bot

apps/paperless-ngx/paperless-ngx-deployment.yaml

@@ -29,7 +29,7 @@ spec:
           type: "RuntimeDefault"
       containers:
         - name: "paperless-ngx"
-          image: "ghcr.io/paperless-ngx/paperless-ngx:2.15.3"
+          image: "ghcr.io/paperless-ngx/paperless-ngx:2.18.4"
           imagePullPolicy: "IfNotPresent"
           resources:
             requests: