Support reproducible XZ Linux archives without changing runtime contents

tools/linux_archive_smoke.py

@@ -25,7 +25,7 @@ def sha256(path):
 
 def extract_checked(archive_path, destination):
     from package_linux import safe_name
-    with tarfile.open(archive_path, "r:gz") as archive:
+    with tarfile.open(archive_path, "r:*") as archive:
         members = archive.getmembers()
         if not 1 <= len(members) <= 128 or len({item.name for item in members}) != len(members):
             raise ValueError("Invalid candidate member inventory")