Updates hydra: c248a31 Fix: docs: minor README improvements

diff --git a/hydra b/hydra
index 4423ea3c480a6a092f843688bc15ee62304885c9..c248a31a9200c0e373365f6ab7d8c75972d3808e 160000 (submodule)
--- a/hydra
+++ b/hydra
@@ -1 +1 @@
-Subproject commit 4423ea3c480a6a092f843688bc15ee62304885c9
+Subproject commit c248a31a9200c0e373365f6ab7d8c75972d3808e