update monero submodule for v0.18.3.4

diff --git a/monero b/monero
index 5d4d1e8f6854baa894f738d373cfee79e6d4eba2..6a88faa9af20c56363bac563a5c0b803ea2695dd 160000 (submodule)
--- a/monero
+++ b/monero
@@ -1 +1 @@
-Subproject commit 5d4d1e8f6854baa894f738d373cfee79e6d4eba2
+Subproject commit 6a88faa9af20c56363bac563a5c0b803ea2695dd