internal/pkg: temporary scratch space for cure

This allows for more flexibility during implementation. The use case that required this was for expanding single directory tarballs.

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

internal/pkg/net.go

@@ -101,7 +101,7 @@ func (a *httpArtifact) do() (data []byte, err error) {
 }
 
 // Cure returns syscall.ENOTSUP. Callers should use Data instead.
-func (a *httpArtifact) Cure(*check.Absolute, CacheDataFunc) error {
+func (a *httpArtifact) Cure(*check.Absolute, *check.Absolute, CacheDataFunc) error {
 	return syscall.ENOTSUP
 }