chore(release): update emqx release version

include/emqx_release.hrl

@@ -29,7 +29,7 @@
 
 -ifndef(EMQX_ENTERPRISE).
 
--define(EMQX_RELEASE, {opensource, "4.3.0"}).
+-define(EMQX_RELEASE, {opensource, "4.3.1"}).
 
 -else.