Deprecate Pages daemon-* flags

What does this MR do?

We have now disabled chroot by default since %14.1, and recently removed support for disk-based configuration coming in %14.3. And we've also removed the chroot completely from Pages.

However, we still support daemonizing and in fact Omnibus still configures Pages to run as daemon https://gitlab.com/gitlab-org/omnibus-gitlab/-/blob/5b4022e03873d3b38b466b17b633812b175fc0fe/files/gitlab-cookbooks/gitlab-pages/templates/default/gitlab-pages-config.erb#L4.

We should deprecate the following flags:

daemon-uid
daemon-gid
daemon-inplace-chroot

And give way to gitlab-pages#133 (closed)

Related issues

Closes #6381 (closed)

Checklist

See Definition of done.

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