Correct assignment of the environment vars

Author: colin-gourlay

Diff for: src/Serilog.Enrichers.Environment/Enrichers/EnvironmentUserNameEnricher.cs

@@ -49,8 +49,8 @@ private static string GetEnvironmentUserName()
             var userDomainName = Environment.UserDomainName;
             var userName = Environment.UserName;
 #else
-            var userDomainName = Environment.GetEnvironmentVariable("USERNAME");
-            var userName = Environment.GetEnvironmentVariable("USERDOMAIN");
+            var userDomainName = Environment.GetEnvironmentVariable("USERDOMAIN");
+            var userName = Environment.GetEnvironmentVariable("USERNAME");
 #endif
             return !string.IsNullOrWhiteSpace(userDomainName) ? $@"{userDomainName}\{userName}" : userName;
         }