WSL does not support SELinux, so at best it's pointless to install. This also actively breaks WSL 1 users, although I don't think we should suggest that we support that, and if the policy on the builder doesn't match the target things break during the build. It also reduced the build time from ~80 seconds to ~70 seconds for me, so that's nice. Signed-off-by: Jeremy Cline <jeremycline@linux.microsoft.com>