guix home does not have a way to uninstall itself

Hi,

guix home does not have a way to uninstall itself.

See the following resources for more context:

help-guix conversation with ludo:

irc conversation about the bug on #tropin on Libera:

```

jgart: symlink-manager have cleanup-symlinks procedure in it, which cleanups dotfiles from previous generation. just declare a new home-environment with empty list of services and add only symlink-manager to essential-services, after that do a reconfigure and everything except ~/.guix-home will be cleaned up

abcdw_: cool! could we make a subcommand from that? guix home uninstall or similar.

jgart: Most people are not going to know to use cleanup-symlinks procedure in symlink-manager.

Thu, Sep 8 2022

abcdw joined the room

jgart: Create a proposal on bug-guix please and cc me, I'll take a look at it, when will get spare time

jgart: will do, thanks!

```

all best,

jgart