fix: Subscription source bugs fix (#1626) (#1633)

Fixes #1620.
Cherry pick of #1626 into develop.

- Add timeouts for websocket operations for connections to rippled.
Without these timeouts if connection hangs for some reason, clio
wouldn't know the connection is hanging.
- Fix potential data race in choosing new subscription source which will
forward messages to users.
- Optimise switching between subscription sources.

src/etl/LoadBalancer.hpp

@@ -25,7 +25,7 @@
 #include "etl/Source.hpp"
 #include "etl/impl/ForwardingCache.hpp"
 #include "feed/SubscriptionManagerInterface.hpp"
-#include "rpc/Errors.hpp"
+#include "util/Mutex.hpp"
 #include "util/config/Config.hpp"
 #include "util/log/Logger.hpp"
 
@@ -39,7 +39,6 @@
 #include <org/xrpl/rpc/v1/ledger.pb.h>
 #include <xrpl/proto/org/xrpl/rpc/v1/xrp_ledger.grpc.pb.h>
 
-#include <atomic>
 #include <chrono>
 #include <cstdint>
 #include <expected>
@@ -76,7 +75,10 @@ private:
     std::optional<ETLState> etlState_;
     std::uint32_t downloadRanges_ =
         DEFAULT_DOWNLOAD_RANGES; /*< The number of markers to use when downloading initial ledger */
-    std::atomic_bool hasForwardingSource_{false};
+
+    // Using mutext instead of atomic_bool because choosing a new source to
+    // forward messages should be done with a mutual exclusion otherwise there will be a race condition
+    util::Mutex<bool> hasForwardingSource_{false};
 
 public:
     /**