Fixes <https://issues.guix.gnu.org/78272>.
Fixes a bug caused by commit ce363c1dc7,
which inadvertently made /tmp read-only as well.
* guix/scripts/environment.scm (launch-environment/container)[tmpfs]:
New variable.
Add it to ‘file-systems’.
* guix/scripts/home.scm (spawn-home-container): Add /tmp file system
to #:mounts.
* tests/guix-environment-container.sh: Add test.
Reported-by: Tomas Volf <~@wolfsden.cz>
Change-Id: I5cb449e6d0c213d4b5866cbcbd14990437a7d4c5
edc799dabf