Don't append Password="*****" if there is no password set; it is just noise!

StackExchange.Redis/StackExchange/Redis/ConfigurationOptions.cs

@@ -489,7 +489,7 @@ public string ToString(bool includePassword)
             Append(sb, OptionKeys.AllowAdmin, allowAdmin);
             Append(sb, OptionKeys.Version, defaultVersion);
             Append(sb, OptionKeys.ConnectTimeout, connectTimeout);
-            Append(sb, OptionKeys.Password, includePassword ? Password : "*****");
+            Append(sb, OptionKeys.Password, (includePassword || string.IsNullOrEmpty(Password)) ? Password : "*****");
             Append(sb, OptionKeys.TieBreaker, tieBreaker);
             Append(sb, OptionKeys.WriteBuffer, writeBuffer);
             Append(sb, OptionKeys.Ssl, ssl);