Prevent file logging before configuration initialization (#7896)

src/Nethermind/Nethermind.Logging.NLog/NLogManager.cs

@@ -20,6 +20,11 @@ public class NLogManager : ILogManager, IDisposable
         private const string DefaultFileTargetName = "file-async_wrapped";
         private const string DefaultFolder = "logs";
 
+        /// <summary>
+        /// The constructor to use when the configuration is not yet initialized.
+        /// </summary>
+        public NLogManager() { /* Log in temp dir? */ }
+
         public NLogManager(string logFileName, string logDirectory = null, string logRules = null)
         {
             Setup(logFileName, logDirectory, logRules);

src/Nethermind/Nethermind.Runner/Program.cs

@@ -348,7 +348,7 @@ void ConfigureLogger(ParseResult parseResult)
         return;
     }
 
-    using NLogManager logManager = new("nethermind.log");
+    using NLogManager logManager = new();
 
     logger = logManager.GetClassLogger();