transport: use connect_timeout for use_keyspace

Our use_keyspace() utility may hang if any of the nodes are not
available. Since the default TCP timeout is rather long (10 minutes
on most systems), let's instead use the existing connection timeout
as the timeout value.

Author: psarna

scylla/src/transport/connection_pool.rs

@@ -1017,6 +1017,7 @@ impl PoolRefiller {
         let mut conns = self.conns.clone();
         let keyspace_name = keyspace_name.clone();
         let address = self.address;
+        let connect_timeout = self.pool_config.connection_config.connect_timeout;
 
         let fut = async move {
             let mut use_keyspace_futures = Vec::new();
@@ -1032,8 +1033,12 @@ impl PoolRefiller {
                 return Ok(());
             }
 
-            let use_keyspace_results: Vec<Result<(), QueryError>> =
-                futures::future::join_all(use_keyspace_futures).await;
+            let use_keyspace_results: Vec<Result<(), QueryError>> = tokio::time::timeout(
+                connect_timeout,
+                futures::future::join_all(use_keyspace_futures),
+            )
+            .await
+            .map_err(|_| QueryError::TimeoutError)?;
 
             // If there was at least one Ok and the rest were IoErrors we can return Ok
             // keyspace name is correct and will be used on broken connection on the next reconnect