feat: support server-side keep-alive for mysql and pg protocols (#5496)

* feat: support server-side keep-alive for mysql and pg protocols

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

* update config.md

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

* update config to use humantime for keep-alive configuration

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

* chore: Update socket2 dependency

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

---------

Signed-off-by: Ruihang Xia <waynestxia@gmail.com>

tests-integration/src/test_util.rs

@@ -589,6 +589,7 @@ pub async fn setup_mysql_server_with_user_provider(
                 ReloadableTlsServerConfig::try_new(opts.tls.clone())
                     .expect("Failed to load certificates and keys"),
             ),
+            0,
             opts.reject_no_database.unwrap_or(false),
         )),
     ));
@@ -641,6 +642,7 @@ pub async fn setup_pg_server_with_user_provider(
         ServerSqlQueryHandlerAdapter::arc(fe_instance_ref),
         opts.tls.should_force_tls(),
         tls_server_config,
+        0,
         runtime,
         user_provider,
     )) as Box<dyn Server>);

tests-integration/tests/http.rs

@@ -923,6 +923,7 @@ watch = false
 enable = true
 addr = "127.0.0.1:4002"
 runtime_size = 2
+keep_alive = "0s"
 
 [mysql.tls]
 mode = "disable"
@@ -934,6 +935,7 @@ watch = false
 enable = true
 addr = "127.0.0.1:4003"
 runtime_size = 2
+keep_alive = "0s"
 
 [postgres.tls]
 mode = "disable"