fixtures: update git submodule to same commit as in py-evm.

veox · veox · commit 1146f83277ff · 2019-05-21T14:52:03.000+03:00
diff --git a/fixtures b/fixtures
@@ -1 +1 @@
-Subproject commit 420f443477caa8516f1f9ee8122fafc3415c0f34
+Subproject commit 6b85703b568f4456582a00665d8a3e5c3b20b484
