chore: update license expiry log

lib-ee/emqx_license/include/emqx_license.hrl

@@ -12,7 +12,7 @@
     "========================================================================\n"
     "Using an evaluation license limited to ~p concurrent connections.\n"
     "Apply for a license at https://emqx.com/apply-licenses/emqx.\n"
-    "Or contact EMQ customer services.\n"
+    "Or contact EMQ customer services via email at contact@emqx.io\n"
     "========================================================================\n"
 ).
 
@@ -21,7 +21,7 @@
     "========================================================================\n"
     "License has been expired for ~p days.\n"
     "Apply for a new license at https://emqx.com/apply-licenses/emqx.\n"
-    "Or contact EMQ customer services.\n"
+    "Or contact EMQ customer services via email at contact@emqx.io\n"
     "========================================================================\n"
 ).