Updates hydra: b50ad39 Fix git-annex initialization at sync-media

diff --git a/hydra b/hydra
index 5a3c8624f2f3bbcc62aef6c0fc1717897ce2ee36..b50ad3991bdd146aa1a184684969b4f6fb53dff2 160000 (submodule)
--- a/hydra
+++ b/hydra
@@ -1 +1 @@
-Subproject commit 5a3c8624f2f3bbcc62aef6c0fc1717897ce2ee36
+Subproject commit b50ad3991bdd146aa1a184684969b4f6fb53dff2