despite suffix, hydra logs don't seem to be bz2-compressed

extended-tests.py

@@ -1,5 +1,4 @@
 import json
-import bz2
 import sys
 
 with open(sys.argv[1], "r") as f:
@@ -10,5 +9,5 @@ assert drv.startswith("/nix/store/")
 drv = drv[len("/nix/store/"):]
 hydra_log = "/var/lib/hydra/build-logs/" + drv[:2] + "/" + drv[2:]
 
-with bz2.BZ2File(hydra_log, "w") as f:
+with open(hydra_log, "w") as f:
     f.write(b"hack successful")