internal/pkg: allow user namespace creation

No good reason to filter this in the execArtifact container, and the extended filter breaks certain programs.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pkg/exec.go

@@ -290,7 +290,7 @@ func (a *execArtifact) cure(f *FContext, hostNet bool) (err error) {
 
 	z := container.New(ctx, f.GetMessage())
 	z.WaitDelay = execWaitDelay
-	z.SeccompPresets |= std.PresetStrict
+	z.SeccompPresets |= std.PresetStrict & ^std.PresetDenyNS
 	z.ParentPerm = 0700
 	z.HostNet = hostNet
 	z.Hostname = "cure"