Updates hydra: 04b21c8 Fix: docs: notes on encrypted backups

diff --git a/hydra b/hydra
index c0369772171a8fc3c209b96ce6e29fc91d8db088..04b21c85f3063654a888d3917cd7ed4689744230 160000 (submodule)
--- a/hydra
+++ b/hydra
@@ -1 +1 @@
-Subproject commit c0369772171a8fc3c209b96ce6e29fc91d8db088
+Subproject commit 04b21c85f3063654a888d3917cd7ed4689744230