Fix MSBuild property evaluation (#355)

Fix MSBuild parameters specified in `aws-lambda-tools-defaults.json` not being used with `Utilities.LookPublishAotFlag()`.
Resolves #351.

src/Amazon.Lambda.Tools/Commands/PackageCommand.cs

@@ -220,7 +220,7 @@ protected override async Task<bool> PerformActionAsync()
                     }
                 }
 
-                bool isNativeAot = Utilities.LookPublishAotFlag(projectLocation, this.MSBuildParameters);
+                bool isNativeAot = Utilities.LookPublishAotFlag(projectLocation, msbuildParameters);
 
                 var architecture = this.GetStringValueOrDefault(this.Architecture, LambdaDefinedCommandOptions.ARGUMENT_FUNCTION_ARCHITECTURE, false);
                 var disableVersionCheck = this.GetBoolValueOrDefault(this.DisableVersionCheck, LambdaDefinedCommandOptions.ARGUMENT_DISABLE_VERSION_CHECK, false).GetValueOrDefault();