Automatic update of common submodule

From a8c8939 to 84d06cd

diff --git a/common b/common
index a8c89390ae462951f3f94997955d5319028f26d3..84d06cd7a0e6b0857009858574aa21bb56309efb 160000 (submodule)
--- a/common
+++ b/common
@@ -1 +1 @@
-Subproject commit a8c89390ae462951f3f94997955d5319028f26d3
+Subproject commit 84d06cd7a0e6b0857009858574aa21bb56309efb