chore: changelog for hibernate_after

apps/emqx/src/emqx.app.src

@@ -3,7 +3,7 @@
     {id, "emqx"},
     {description, "EMQX Core"},
     % strict semver, bump manually!
-    {vsn, "5.0.17"},
+    {vsn, "5.0.18"},
     {modules, []},
     {registered, []},
     {applications, [

changes/v5.0.18/perf-9967-en.md

@@ -0,0 +1 @@
+New common TLS option 'hibernate_after' to reduce memory footprint per idle connecion, default: 5s.

changes/v5.0.18/perf-9967-zh.md

@@ -0,0 +1 @@
+新的通用 TLS 选项 'hibernate_after'， 以减少空闲连接的内存占用，默认： 5s 。