New bugfix release 2.39.2
Small bugfix release:
- debian: rework how we run autopkgtests
- interfaces/docker-support: add overlayfs accesses for ubuntu core
- data/selinux: permit init_t to remount snappy_snap_t
- strutil/shlex: fix ineffassign
- packaging: fix build-depends on powerpc
The most important change the the selinux fix for fedora.