hydra: disable logs compression plugin as it badly conflicts with upl…

…oad_logs_to_binary_cache

Both try to process the raw log file and unlink() it when they're done.
When both are enabled, and when the `hydra-notify` process isn't stuck,
they race for which one will happen first, and we're uninterested in
keeping the log files locally on hydra.nixos.org.

delft/hydra.nix

@@ -42,6 +42,7 @@ in
       xxx-jobset-repeats = nixos:reproducibility:1
 
       upload_logs_to_binary_cache = true
+      compress_build_logs = false  # conflicts with upload_logs_to_binary_cache
 
       log_prefix = https://cache.nixos.org/