[master] Bump 3rdparty ref

Signed-off-by: Lukas Reschke <lukas@statuscode.ch>

diff --git a/3rdparty b/3rdparty
index a39c1fd340a095c0814ddf5db2d7f97a592a2d16..6876f1fce8d1c70790c165dd7ed0b4214364e397 160000 (submodule)
--- a/3rdparty
+++ b/3rdparty
@@ -1 +1 @@
-Subproject commit a39c1fd340a095c0814ddf5db2d7f97a592a2d16
+Subproject commit 6876f1fce8d1c70790c165dd7ed0b4214364e397