pkg/archive: use more narrow interface for CompressStream

Signed-off-by: Alexander Morozov <lk4d4@docker.com>

pkg/archive/archive.go

@@ -193,7 +193,7 @@ func DecompressStream(archive io.Reader) (io.ReadCloser, error) {
 }
 
 // CompressStream compresses the dest with specified compression algorithm.
-func CompressStream(dest io.WriteCloser, compression Compression) (io.WriteCloser, error) {
+func CompressStream(dest io.Writer, compression Compression) (io.WriteCloser, error) {
 	p := pools.BufioWriter32KPool
 	buf := p.Get(dest)
 	switch compression {