Do not try to reload the systemd daemon when we are using --no-start-daemon

[Hoverbear]

Description

When we are using --no-start-daemon (such as in a systemd enabled podman container that is in podman build phase) we do not need to run systemctl daemon-reload, in fact we cannot without getting an error.

My test Dockerfile:

FROM ubuntu:latest
RUN apt update -y
RUN apt install curl systemd -y
COPY nix-installer /nix-installer
RUN /nix-installer install linux --extra-conf "sandbox = false" --no-start-daemon --no-confirm
ENV PATH="${PATH}:/nix/var/nix/profiles/default/bin"
RUN nix run nixpkgs#hello
CMD [ "/usr/sbin/init" ]

Checklist

• Formatted with cargo fmt
• Built with nix build
• Ran flake checks with nix flake check
• Added or updated relevant tests (leave unchecked if not applicable)
• Added or updated relevant documentation (leave unchecked if not applicable)
• Linked to related issues (leave unchecked if not applicable)

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