Fix build errors due to missing include

Errors were:

| connectivity.cpp:151:42:   required from here
| sublogger.hpp:42:9: error: no matching function for call to '=::log(spdlog::level::level_enum&, std::string&, const std::__cxx11::basic_string<char>&)'
|    42 |         log_->log(lvl, prefix_, args...);
|       |         ^~~~

| topic_subscriptions.cpp:54:37:   required from here
| sublogger.hpp:42:9: error: no matching function for call to 'spdlog::logger::log(spdlog::level::level_enum&, std::string&, const std::__cxx11::basic_string<char>&, const long long unsigned int&, const long long unsigned int&)'
|    42 |         log_->log(lvl, prefix_, args...);
|       |         ^~~~

| remote_subscriptions.cpp:28:56:   required from here
| sublogger.hpp:42:9: error: no matching function for call to 'spdlog::logger::log(spdlog::level::level_enum&, std::string&, const std::__cxx11::basic_string<char>&)'
|    42 |         log_->log(lvl, prefix_, args...);
|       |         ^~~~

| kad_server.cpp:40:42:   required from here
| sublogger.hpp:42:9: error: no matching function for call to 'spdlog::logger::log(spdlog::level::level_enum&, std::string&, const std::__cxx11::basic_string<char>&)'
|    42 |         log_->log(lvl, prefix_, args...);
|       |         ^~~~

Author: eigendude

src/protocol/gossip/impl/connectivity.cpp

@@ -12,6 +12,8 @@
 #include <libp2p/protocol/gossip/impl/message_builder.hpp>
 #include <libp2p/protocol/gossip/impl/message_receiver.hpp>
 
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   namespace {

src/protocol/gossip/impl/gossip_core.cpp

@@ -12,6 +12,8 @@
 #include <libp2p/protocol/gossip/impl/message_builder.hpp>
 #include <libp2p/protocol/gossip/impl/remote_subscriptions.hpp>
 
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   // clang-format off

src/protocol/gossip/impl/remote_subscriptions.cpp

@@ -10,6 +10,9 @@
 #include <libp2p/protocol/gossip/impl/connectivity.hpp>
 #include <libp2p/protocol/gossip/impl/message_builder.hpp>
 
+#define SPDLOG_TRACE_ON
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   RemoteSubscriptions::RemoteSubscriptions(const Config &config,

src/protocol/gossip/impl/stream_reader.cpp

@@ -14,6 +14,8 @@
 #define TRACE_ENABLED 1
 #include <libp2p/common/trace.hpp>
 
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   StreamReader::StreamReader(const Config &config,

src/protocol/gossip/impl/stream_writer.cpp

@@ -13,6 +13,8 @@
 #define TRACE_ENABLED 1
 #include <libp2p/common/trace.hpp>
 
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   StreamWriter::StreamWriter(const Config &config,

src/protocol/gossip/impl/topic_subscriptions.cpp

@@ -11,6 +11,9 @@
 #include <libp2p/protocol/gossip/impl/connectivity.hpp>
 #include <libp2p/protocol/gossip/impl/message_builder.hpp>
 
+#define SPDLOG_TRACE_ON
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::gossip {
 
   namespace {

src/protocol/kademlia/impl/kad_impl.cpp

@@ -8,6 +8,8 @@
 #include <libp2p/network/connection_manager.hpp>
 #include <libp2p/protocol/kademlia/impl/kad_server.hpp>
 
+#include <spdlog/spdlog.h>
+
 OUTCOME_CPP_DEFINE_CATEGORY(libp2p::protocol::kademlia, Error, e) {
   using E = libp2p::protocol::kademlia::Error;
   switch (e) {

src/protocol/kademlia/impl/kad_server.cpp

@@ -8,6 +8,8 @@
 #include <libp2p/network/connection_manager.hpp>
 #include <libp2p/protocol/kademlia/impl/kad_server.hpp>
 
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol::kademlia {
 
   std::array<KadServer::RequestHandler, Message::kTableSize>

src/protocol_muxer/multiselect/multiselect.cpp

@@ -8,6 +8,9 @@
 #define TRACE_ENABLED 1
 #include <libp2p/common/trace.hpp>
 
+#define SPDLOG_TRACE_ON
+#include <spdlog/spdlog.h>
+
 namespace libp2p::protocol_muxer {
   using peer::Protocol;