fix: set oom_score_adj to -1000 and document in all docker run commands

Agent-Logs-Url: https://github.com/nextcloud/all-in-one/sessions/40122d48-db6c-4993-a220-40597fcf8262

Co-authored-by: szaimen <42591237+szaimen@users.noreply.github.com>

multiple-instances.md

@@ -143,6 +143,7 @@ apt install --no-install-recommends qemu-system qemu-utils libvirt-clients libvi
    --sig-proxy=false \
    --name nextcloud-aio-mastercontainer \
    --restart always \
+   --oom-score-adj -1000 \
    --publish 8080:8080 \
    --env APACHE_PORT=11000 \
    --env APACHE_IP_BINDING=0.0.0.0 \