refactor: use async tag to denote async calls or operations

tests/stresstests/concatenator-proxy.h

@@ -44,7 +44,8 @@ protected:
 public:
     sdbus::PendingAsyncCall concatenate(const std::map<std::string, sdbus::Variant>& params)
     {
-        return proxy_->callMethodAsync("concatenate").onInterface(INTERFACE_NAME).withArguments(params).uponReplyInvoke([this](const sdbus::Error* error, const std::string& result){ this->onConcatenateReply(result, error); });
+        using sdbus::async;
+        return proxy_->callMethod("concatenate", async).onInterface(INTERFACE_NAME).withArguments(params).uponReplyInvoke([this](const sdbus::Error* error, const std::string& result){ this->onConcatenateReply(result, error); });
     }
 
 private:

tests/stresstests/sdbus-c++-stress-tests.cpp

@@ -481,7 +481,7 @@ int main(int argc, char *argv[])
             // We could run the loop in a sync way, but we want it to run also when proxies are destroyed for better
             // coverage of multi-threaded scenarios, so we run it async and use condition variable for exit notification
             //con.enterEventLoop();
-            con.enterEventLoopAsync();
+            con.enterEventLoop(sdbus::async);
 
             std::unique_lock<std::mutex> lock(clientThreadExitMutex);
             clientThreadExitCond.wait(lock, [&]{return clientThreadExit;});