test(batch18): port behavioral batch-18 tests

dotnet/tests/ZB.MOM.NatsNet.Server.Tests/ImplBacklog/NatsServerTests.cs

@@ -44,6 +44,25 @@ public sealed class NatsServerTests
         result.Error.ShouldBe(ServerErrors.ErrAccountValidation);
     }
 
+    [Fact] // T:2897
+    public void InsecureSkipVerifyWarning_ShouldSucceed()
+    {
+        var (tlsOptions, parseError) = ServerOptions.ParseTLS(
+            new Dictionary<string, object?>
+            {
+                ["insecure"] = true,
+            },
+            isClientCtx: true);
+
+        parseError.ShouldBeNull();
+        tlsOptions.ShouldNotBeNull();
+        tlsOptions!.Insecure.ShouldBeTrue();
+
+        var (tlsConfig, tlsError) = ServerOptions.GenTLSConfig(tlsOptions);
+        tlsError.ShouldBeNull();
+        tlsConfig.ShouldNotBeNull();
+    }
+
     [Fact] // T:2886
     public void CustomRouterAuthentication_ShouldSucceed()
     {