docs: improve descriptions

Co-authored-by: Zaiming (Stone) Shi <zmstone@gmail.com>

apps/emqx/i18n/emqx_schema_i18n.conf

@@ -1824,8 +1824,8 @@ server_ssl_opts_schema_enable_crl_check {
 crl_cache_refresh_http_timeout {
     desc {
         en: "The timeout for the HTTP request when fetching CRLs.  This is"
-            " global for all listeners."
-        zh: "获取 CRLs 时 HTTP 请求的超时。 这对所有监听器来说是全局的。"
+            " a global setting for all listeners."
+        zh: "获取 CRLs 时 HTTP 请求的超时。 该配置对所有启用 CRL 检查的监听器监听器有效。"
     }
     label: {
         en: "CRL Cache Refresh HTTP Timeout"
@@ -1835,9 +1835,9 @@ crl_cache_refresh_http_timeout {
 
 crl_cache_refresh_interval {
     desc {
-        en: "The period to refresh the CRLs from the servers.  This is global"
+        en: "The period to refresh the CRLs from the servers.  This is a global setting"
             " for all URLs and listeners."
-        zh: "从服务器刷新CRL的周期。 这对所有URL和监听器来说是全局性的。"
+        zh: "从服务器刷新CRL的周期。 该配置对所有 URL 和监听器有效。"
     }
     label: {
         en: "CRL Cache Refresh Interval"

apps/emqx/src/emqx_schema.erl

@@ -230,7 +230,7 @@ roots(low) ->
         {"crl_cache",
             sc(
                 ref("crl_cache"),
-                #{}
+                #{hidden => true}
             )}
     ].
 
@@ -809,7 +809,6 @@ fields("crl_cache") ->
             sc(
                 duration(),
                 #{
-                    hidden => true,
                     default => <<"15m">>,
                     desc => ?DESC("crl_cache_refresh_interval")
                 }
@@ -818,7 +817,6 @@ fields("crl_cache") ->
             sc(
                 duration(),
                 #{
-                    hidden => true,
                     default => <<"15s">>,
                     desc => ?DESC("crl_cache_refresh_http_timeout")
                 }
@@ -827,7 +825,6 @@ fields("crl_cache") ->
             sc(
                 pos_integer(),
                 #{
-                    hidden => true,
                     default => 100,
                     desc => ?DESC("crl_cache_capacity")
                 }