chore(nextcloud): Upgrade Nextcloud to 26.0.3

charts/nextcloud/Chart.yaml

 apiVersion: v2
 name: nextcloud
-version: 3.2.3
+version: 3.3.0
 # renovate: image=docker.io/library/nextcloud
-appVersion: "25.0.8"
+appVersion: "26.0.3"
 description: A file sharing server that puts the control and security of your own data back into your hands.
 keywords:
 - nextcloud